Extracted from

U.S. MARINES IN VIETNAM: Fighting The North Vietnamese 1967

By Telfer, Rogers and Fleming,

History and Museums Division,

HQMC, Washington DC, 1984



Chapter 3

Combined US/ARVN Operations in the DMZ



Operation Prairie IV Begins


Enemy concentrations of troops and artillery in the DMZ area dictated the reinforcement of the 3d Marine Division. Responding to the demands of the situation, MACV deployed Army Task Force Oregon to the southern two provinces of I Corps in April to allow Marine units to reinforce the northern three provinces. As a result of the northward shift of Marine forces, Colonel Robert M. Jenkins’ 9th Marines headquarters moved from Da Nang to Dong Ha during 12-16 April. At the same time, III MAF shifted the 2d Battalions of the 4th and 26th Marines from the 1st Marine Division area to the vicinity of Phu Bai


The introduction of a second regimental headquarters into Quang Tri Province permitted the closing of the 3d Division’s forward command post at Dong Ha after the conclusion of Operation Prairie III. Units operating from Dong Ha reverted to the operational control of the 9th Marines, while the 3d Marines controlled those operating from Camp Carroll.


Operation Prairie IV started on 20 April as a two-regiment search and destroy operation, covering the same area as Prairie III. The concept of employment placed the 3d Battalion, 3d Marines and the 3d Battalion, 9th Marines in the northwest portion of the area of operations. The 9th Marines, using the 1st Battalions of the 4th and 9th Marines, was to cover the vital piedmont area in and around Quang Tri City. The boundary between the two units was just west of the Cam Lo-Con Thien axis.


Initially, the operation confined all units to relatively fixed positions. Lieutenant Colonel Wilson’s 3d Battalion, 9th Marines was charged with the security of Camp Carroll and the outpost at Mai Loc.  Wilder’s 3d Battalion, 3d Marines held the Rockpile and placed companies at Ca Lu and Ba Long. The latter battalion was also responsible for providing security for the 11th Engineers, who kept Route 9 open into Khe Sanh.  In the 9th Marines’ area of operation, the 1st Battalion, 9th Marines defended the Dong Ha combat base and provided one company for security of the Cua Viet petroleum, oil, and lubricants (POL) facility.  The 1st Battalion, 4th Marines protected the engineers clearing the trace between Gio Linh and Con Thien, referred to as “Ryan’s Road” because of Brigadier General Michael P. Ryan’s frequent visits and interest in the project. The battalion also continued to provide a company for security for the Gio Linh Composite Artillery Battalion.

Although contact with enemy infantry was light at the beginning of the operation, reconnaissance reports indicated an NVA buildup northwest of the Rockpile. Mortar, rocket, and artillery attacks continued against the Marines clearing “Ryan’s Road,” as well as against the Con Thien and Gio Linh outposts. Attacks on these two positions and against Lieutenant Colonel Willis’ 1st Battalion, 4th Marines and the engineers became almost daily affairs, and included not only mortar and rocket fire from the southern half of the DMZ, but also medium and heavy artillery fire from a growing number of fortifications north of the Ben Hai River.


On 24 April a major battle broke out in the western DMZ near Khe Sanh, the beginning of heavy fighting which continued throughout the summer all along the demarcation line. In conjunction with the battle being fought in the west, the enemy stepped up activity in the east. Enemy forces cut Route 9 between Cam Lo and Khe Sanh repeatedly in an effort to isolate the Marines in that area. In consort with this effort, the NVA attacked the Marine installations at Gio Linh, Camp Carroll, and Dong Ha with mortars, rockets, and artillery. The period 27-28 April was particularly savage. Approximately 850 rounds of artillery, plus 200 mortar rounds blasted Gio Linh, while more than 50 140mm rockets hit Dong Ha.


Attack on Con Thien


On 8 May, the 13th anniversary of the fall of Dien Bien Phu, the NVA tried to overrun the Marine position at Con Thien. The outpost, less than two miles from the southern boundary of the DMZ, was on a hill only 158 meters high in the middle of a red mud plain. It afforded the best observation in the area, overlooking the DMZ to the north and west, as well as the Marine base at Dong Ha to the southeast. As a strategic terrain feature, Con Thien was important to the Communists; before the summer was over, it achieved an additional symbolic importance.

At the time of the attack, the outpost contained a small command group of the 1st Battalion, 4th Marines, reinforced companies A and D of the battalion, and a civilian irregular defense group (CIDG) unit. The Marines were there to provide security for the engineers, who, having completed the trace on 1 May, were busy clearing a 500-meter-wide strip around the perimeter of the outpost. At 0255, the morning of 8 May, a green flare lit the sky south of the hill, followed immediately by a savage 300-round mortar and artillery attack. Concurrently, Camp Carroll, Gio Linh, and Dong Ha also came under fire.


At Con Thien, enemy units maneuvering under cover of the barrage breached the defensive wire with bangalore torpedoes, and small elements moved inside. At approximately 0400, two NVA battalions, armed with flamethrowers, RPGs, and automatic weapons, attacked through the breach in the wire. The brunt of this assault fell on the right flank of Company D. The Marines engaged the enemy force in bitter hand-to-hand fighting. An engineer platoon moved to reinforce Company D. The situation became serious when the Marines ran out of 81mm mortar illumination rounds; artillery illumination from the nearest artillery at Gio Linh could not reach Con Thien.1/  A flare plane finally arrived and provided much-needed illumination until daylight.


Meanwhile, Company A sent a platoon to help Company D, as well as to protect an ammunition resupply convoy composed of an attached Army M42 “Duster,” two LVTHs, and two 1/4-ton trucks. As these elements moved up to support the hard-pressed Marines of Company D, the relief vehicles came under enemy fire. The Army M42, which was the lead vehicle, stopped and burst into flames after being hit by an enemy RPG antitank projectile. A satchel charge exploded under the following LVTH. It began to burn but its crew managed to get out. The trailing LVTH, trying to get around the burning vehicles, which now included the 1/4-ton trucks, became entangled by barbed wire around its left rear sprocket. The tractor was stuck. Despite their losses, the reinforcing Marines continued to Company D’s position. With these reinforcements, Company D halted the enemy penetration and sealed off the break in the wire just before daylight. By 0900, the enemy soldiers still within the perimeter were either dead or captured.’


The recently completed brush clearance around the perimeter paid early dividends. It permitted the Marines to catch the retreating North Vietnamese in the open as they crossed the cleared strip. Tanks and LVTHs firing both conventional and “beehive” antipersonnel ammunition were particularly effective. Supporting fires of the Composite Artillery Battalion at Gio< Linh ripped into the enemy as it withdrew north to the DMZ.


The defending Marines lost 44 killed and 110 wounded, as well as two LVTHs and one 1/4-ton truck destroyed, but the hard and bloody battle cost the enemy 197 killed and 8 captured. The Communists left behind 72 weapons, including 19 antitank weapons, 3 light machine guns, and 3 flamethrowers. 2/

The 8 May attack on Con Thien had been carefully rehearsed, but the enemy displayed an inherent inability to alter plans. The NVA attacked the strongest point of the defensive perimeter and continued to press the attack at this point, even when it was clear that it had encountered heavier resistance than anticipated. The enemy planners were not aware of the arrival of the two Marine companies. Company D had replaced an ARVN unit only a few days before the attack.


Following this battle, enemy activity intensified throughout the “Leatherneck Square” area.3/ The number and volume of artillery attacks increased greatly. More than 4,200 mortar, rocket, and artillery rounds were fired at Marine positions during the month. The enemy revealed the degree and sophistication of its buildup in the area on 10 May by the destruction of a Douglas A-4E Skyhawk flying a radar-controlled mission near the southern boundary of the DMZ. As the plane approached its target, Marines on the ground witnessed the firing of three surface-to-air missiles (SAM) from positions north of the Ben Hai River. One of the missiles hit the A-4E; the aircraft disappeared from the controlling radar screen at Dong Ha. This was the first reported use of Communist SAMs over South Vietnam. 


Into the DMZ


Enemy ground action increased. During the period 13-16 May, while clearing Route 561 from Cam Lo to Con Thien, the 1st Battalion, 9th Marines made heavy contact with a large NVA force in well prepared positions just south of Con Thien. The enemy fought well and retired north of the DMZ boundary only after extreme pressure.

Once again the enemy used the unusual advantage conferred by the de facto access to the DMZ, and thus to all of South Vietnam. Marine forces still were forbidden by U.S. policy to move beyond the southern edge of the DMZ. For some time much of the shelling, particularly that by shorter-ranged weapons, mortars, and rockets, came from the region south of the Ben Hai River. It was equally clear that the enemy was using the southern DMZ as a sanctuary from which to launch ground attacks, such as the one against Con Thien.

On 8 May, after the Con Thien attack, Washington changed the DMZ policy. MACV then authorized III MAF to conduct ground operations in the southern half of the DMZ, and III MAF, in conjunction with the South Vietnamese, quickly drew up plans for combined USMC/ARVN ground, amphibious, and heliborne operations in the eastern portion of the area. The basic concept called for ground attacks by the 3d Marine Division and 1st ARVN Division along parallel routes, as far north as the Ben Hai River.

Combined with the ground attack, the newly formed Special Landing Force Alpha was to conduct an amphibious landing in the southern portion of the DMZ along the coast to secure the area as far north as the south bank of the Ben Hai River. 4/   On reaching the Ben Hai, all units were to turn around and attack south on a broad front, sweeping as far as Route 9, destroying all enemy units, installations, and supplies encountered. In addition, the plan included the development of a freefire zone which involved the evacuation by South Vietnamese National Police of some 12,000 noncombatants living within the buffer zone. Operational code names were Hickory for the 3d Marine Division units, Beau Charger and Belt Tight for the SLFs, and Lam Son 54 5/ for the ARVN forces. The ARVN force for this operation was composed of three battalions of airborne troops and two battalions of the 1st ARVN Division. The combined operation was to start on 18 May. More fire support was allocated for this operation than for any previous operation in the 3d Division’s operating area.

The available fire support included artillery, augmented by the 1st Marine Aircraft Wing, two cruisers, and seven destroyers (six U.S. and one Australian), as well as by aircraft from the Seventh Air Force and the Seventh Fleet. The majority of the support focused on enemy concentrations and gun positions in the northern portion of the DMZ and the adjacent area to the immediate north, and, if required, as counterbattery fire against North Vietnamese shore batteries.


A buildup of Marine forces in the Prairie area preceded the operation. Lieutenant Colonel Charles R. Figard’s 2d Battalion, 26th Marines arrived from Phong Dien on 15 May; the 3d Battalion, 4th Marines, commanded by Lieutenant Colonel Wendell N. Vest, came in from Okinawa on the 15th; and the 2d Battalion, 9th Marines, commanded by Lieutenant Colonel John J. Peeler, arrived from Phu Bai on the l6th.6/ At the beginning of the operation three battalions, the 1st Battalion, 4th Marines and the 1st and 3d Battalions, 9th Marines provided augmentation from Operation Prairie IV forces. In addition, SLF Bravo was to act as 3d Division Reserve. The same day Colonel Edward E. Hammerbeck, the new regimental commander, deployed the 9th Marines command post to a position just north of Cam Lo.


During the night of 17-18 May the NVA directed heavy mortar, rocket, and artillery attacks against all Marine positions along the DMZ. Gio Linh and Dong Ha suffered the most. From 2350 on the 17th until 0401 on the 18th, over 300 rounds hit Gio Linh, killing 1 Marine and wounding 12 others. During the attack on Dong Ha, at 0315, 150 140mm rockets killed 11 and wounded 91. One rocket scored a direct hit on the roof of the 3d Marine Division Combat Operations Center (COC), but there were no casualties. The rocket detonated prematurely upon hitting a tin roof the division recently had built a few feet above the original sandbagged but leaky roof. Next door, the ARVN COC had no sandbag protection and suffered numerous casualties. The rockets also damaged considerable amounts of equipment, including minor fragment damage to several helicopters of Major Marvin E. Day’s Marine Medium Helicopter Squadron 363.7/ The Communist artillery attacks, nevertheless, were fortuitous for they allowed the allied forces to bombard the NVA positions in and north of the DMZ, under the guise of counterbattery fire, thereby maintaining tactical surprise for the forthcoming operation.






Operation Lam Son 54


Hickory/Lam Son 54 started on schedule. The 1st ARVN Division elements jumped off at 0500, moving in column up Route 1, into the DMZ. Surprise was complete; the ARVN units encountered no resistance as they moved to the Ben Hai and wheeled south. The two 1st ARVN Division battalions started their sweep south on the east side of Route 1, while the three airborne battalions, supported by tanks, turned to the west and then southward abreast the advance of the 1st Division units east of the highway.

On the 19th, the airborne battalions engaged elements of the 31st and 812th NVA Regiments. From then until the 27th, when Lam Son 54 ended, ARVN units were in constant contact with the enemy. Their casualties were 22 killed and 122 wounded. The enemy suffered more substantial losses: 342 killed, 30 captured, and 51 weapons seized. Most of the casualties occurred in the area known as the “rocket belt” north of Dong Ha.


Operation Beau Charger


East of the Lam Son 54 operational area, Operation Beau Charger began at the scheduled L-hour and H-hour of 0800, 18 May. Just before and during the launching of the assault, a duel started between Navy fire support ships and NVA shore batteries. Although the NVA batteries hit no ships, 10 salvos bracketed the USS Point Defiance (LSD 31). After return fire silenced the shore batteries, the surface landing proceeded without further incident; there was no opposition.

The Beau Charger heliborne force experienced a different reception. Landing Zone Goose was a “hot” zone, and only one platoon of Company A, the assault company, managed to land. The Communists closed in and the situation was very much in doubt. At 1100 elements of Company D and the rest of Company A, reinforced with tanks, succeeded in joining up with the isolated assault platoon. The Communists withdrew only after air strikes began to hammer their positions.

On the 18th, NVA gunners ranged in on supporting Marine SLF artillery positions, knocking out two guns. Ships of the Seventh Fleet returned fire, silencing the North Vietnamese batteries. The Marines relocated their remaining guns at positions 5,800 meters further south.

Action during the rest of Beau Charger consisted of light contact and continuing artillery harassment until the operation ended on 26 May. West of the Beau Charger operational area the 3d Marine Division was faced with a much different situation. There, the enemy had come to fight.


Operation Hickory


Adjacent to the Lam Son 54/Beau Charger operational area, 3d Marine Division units launched Operation Hickory on the morning of 18 May. Lieutenant Colonel Figard’s 2d Battalion, 26th Marines and Lieutenant Colonel Peeler’s 2d Battalion, 9th Marines, supported by tanks and Ontos, advanced northward from positions near Con Thien.8/ Concurrently, Lieutenant Colonel Vest’s 3d Battalion, 4th Marines moved by helicopters into a landing zone (LZ) within the DMZ near the Ben Hai River, northwest of Con Thien. The heliborne battalion was to act as a blocking force to prevent the enemy from escaping to the north, or to stop the movement of reinforcements into the area from the north.

Shortly after 1100 the lead element of Figard’s 2d Battalion, 26th Marines made contact with a force which intelligence officers later determined to have been two battalions. All elements of the Marine battalion quickly became engaged in the battle; the enemy defended from well prepared bunkers and trenches. As the battalion moved against the NVA positions, the right flank came under vicious automatic weapons and mortar fire. Casualties were heavy. Among them were Lieutenant Colonel Figard and his S-3, both of whom required evacuation. Despite the heavy enemy fire, the Navy hospital corpsmen continued their treatment of the wounded. By 1600, Peeler’s 2d Battalion, 9th Marines had moved up on the right of the 2d Battalion, 26th Marines and was also in close contact. Fighting continued until nightfall when the Marines broke contact and pulled back to evacuate casualties. During the day, enemy fire killed 5 Marines and wounded 142; 31 enemy soldiers were known to have been killed.

The 3d Marine Division already had replaced the wounded Lieutenant Colonel Figard with a new battalion commander. As soon as it learned of Figard’s condition, the division immediately ordered Lieutenant Colonel William J. Masterpool, who had just joined the division staff after command of 3d Battalion, 4th Marines, to assume command of the 2d Battalion, 26th Marines.

That night, 75 radar-controlled air strikes hit the NVA positions in front of the two Marine battalions. At 0500 on 19 May, heavy artillery fire fell on the enemy defenses and both battalions jumped off in the attack at 0700. During the “prep” fires several short rounds landed on Company F, 2d Battalion, 9th Marines, killing 3 and wounding 2 Marines. Within minutes, the 2d Battalion, 26th Marines again checked its advance because of savage fire from its front and right, while Peeler’s battalion encountered only light small arms fire and pushed rapidly ahead to relieve the pressure on Masterpool’s flank. By 1030 the 2d Battalion, 26th Marines had overrun the enemy bunker complex, accounting for 34 North Vietnamese killed and 9 wounded.

During the rest of the morning both battalions continued to advance against negligible resistance. At 1330, Captain Robert J. Thompson’s Company H, 2d Battalion, 9th Marines, on the easternmost flank of the advance, met heavy automatic weapon and mortar fire from the east. The company returned fire, but then received additional enemy fire from a tree line 60 meters to the front. Again the Marines returned fire and a tank moved up in support. It silenced the enemy with cannister fire. A squad sent forward to check out the area also came under heavy automatic weapons fire. The tank, moving to support the squad, halted after being hit by RPG rounds and began to burn. A second tank maneuvered forward to help; RPGs disabled it also. Captain Thompson, unable to use other supporting arms because of wounded Marines to his front, moved the entire company forward to retrieve the dead and wounded. After moving the wounded to the rear, the company pulled back and called in supporting arms fire on the evacuated area. The action cost the Marines 7 killed and 12 wounded; enemy casualties were unknown.

In the meantime, Lieutenant Colonel Vest’s 3d Battalion, 4th Marines, after the heavy action involving the 2d Battalions, 26th and 9th Marines, swept to the southeast to block the NVA withdrawal. On 18 May the battalion made little contact, but discovered a large, abandoned, fortified position, well stocked with food and equipment. For the next two days Vest’s battalion maneuvered toward the other Marine battalions which were moving north. Contact was light, but the battalion encountered intermittent mortar and artillery fire. The battalion continued to uncover large caches of rice and ammunition—over 30 tons of rice and 10 tons of ammunition— but due to the heat and distance to the landing zones much of the rice could not be moved and had to be destroyed.9/


To the southwest, Lieutenant Colonel Wilson’s 3d Battalion, 9th Marines, screening the western or left flank of the operation, saw little action during the first two days. Then, on 20 May, Company K, point for the battalion, made contact with what it initially estimated to be an enemy platoon deployed in mutually supporting bunkers in a draw. The enemy, at least a company, took Company K under fire. To relieve pressure on Company K, Company L maneuvered to the flank of the enemy position, but was unable to link up with Company K because of heavy enemy fire. Both companies spent the night on opposite sides of the draw with the enemy force between them, while supporting arms pounded the enemy position all night.


On the 21st, Company M moved forward and joined with K and L and the three companies were able to clear the area. The clearing operation was costly: 26 Marines were killed and 59 wounded. The Marines counted only 36 enemy bodies, but the lingering smell in the draw indicated that many others were in the destroyed fortifications.


Meanwhile, the division reserve, SLF Bravo’s BLT 2/3, commanded by Lieutenant Colonel DeLong, and HMM-164, commanded by Lieutenant Colonel Rodney D. McKitrick, joined Operation Hickory on the 20th. The employment of SLF Bravo involved a unique departure from the norm for amphibious operations in that the heliborne force passed to the control of the 3d Marine Division as it crossed the high water mark. This procedure ensured positive control of all supporting arms covering the battalion’s approach to its inland tactical area of responsibility (TAOR). 10/


The squadron helilifted the battalion into the DMZ northwest of Gio< Linh to block possible withdrawal routes of NVA units then engaged with ARVN airborne formations to the east. By noon all elements of the battalion were ashore and sweeping north toward the DMZ. The Marines of BLT 2/3 encountered only light resistance from small NVA units, apparently security elements for several large ordnance caches and bunker complexes. One of the bunkers was exceptionally sophisticated, constructed of steel overhead and walls. The Marines captured more than 1,000 60mm mortar rounds, as well as large quantities of small arms ammunition and medical supplies in the same complex.


After sweeping the southern bank of the Ben Hai River, DeLong’s battalion wheeled south and began a deliberate search in that direction. Although the battalion met no resistance, it did uncover and destroy two extensive subterranean bunker complexes filled with supplies and ordnance. On the 23d the advance halted temporarily because of the declaration of a cease-fire to be observed throughout Vietnam in honor of Buddha’s birthday.


After the brief “stand down,” two battalions, the 3d Battalion, 4th Marines and the 2d Battalion, 26th Marines, began sweeping the DMZ to the southwest toward the mountains west of Con Thien. The 3d Battalion, 9th Marines continued to move northwest as the other two battalions moved south. To the east, the remaining Hickory battalions resumed search and destroy operations in the southern half of the DMZ and “Leatherneck Square.”


Early on the morning of 25 May, Captain John J. Rozman’s Company H, 26th Marines made contact with a large NVA company in a mutually supporting bunker complex near Hill 117, three miles west of Con Thien. The action was extremely close and lasted for more than an hour before Rozman’s Marines managed to gain fire superiority and disengaged to evacuate their casualties. Air and artillery then hit the enemy positions. When relieved of its casualties, Company H maneuvered north of the hill mass where it met Captain John H. Flathman’s Company K, 3d Battalion, 4th Marines at 1345. Both companies moved against the hill. At 1500 savage fighting developed; the Marines estimated the enemy force holding the position to be at least several companies.


When the Marines could not break through the strongly fortified position, Lieutenant Colonel Masterpool ordered them to disengage so that supporting arms could again attack the enemy positions.”11/  The two Marine companies again attacked but broke off the action at 1730 and established night positions north and west of the hill. Results of the day’s fighting were 14 Marines killed and 92 wounded; the Marines counted 41 NVA bodies.


Marine air and artillery pounded the hill all night in preparation for the next attack, scheduled for the next day. At 0915 on the 26th, enemy automatic weapons fire forced down a UH-1E helicopter on a reconnaissance flight over the area. Among the wounded in the helicopter were Lieutenant Colonel Masterpool, his executive officer, and the commanders of Companies H and K; Lieutenant Colonel Masterpool and Captain Flathman had to be evacuated. Consequently, the battalion delayed the attack for another day to allow time for further bombardment of the hill and command adjustments. On the 27th, Companies E and F, 2d Battalion, 26th Marines, under the control of Lieutenant Colonel Vest’s 3d Battalion, 4th Marines, moved against the objective behind covering artillery fire. They met no resistance and secured the hill by 1600. The 3d Battalion, 4th Marines then passed through Companies E and F and consolidated on the ridges leading up to the higher ground west of Hill 117. In the meanwhile, Lieutenant Colonel Duncan D. Chaplin III arrived by helicopter to assume command of the 2d Battalion, 26th Marines, temporarily under its executive officer, Major James H. Landers.


During the night, Colonel James R. Stockman, the commander of the 3d Marines, initiated heavy artillery fires from Con Thien and Gio Linh and using the 175mm guns of the Army’s 2d Battalion, 94th Artillery to “literally change the face of the earth” on the enemy-held high ground. The following morning, the 3d Battalion, 4th Marines continued its westward movement onto the high ground without opposition. Lieutenant Colonel Vest’s men encountered only the extensive destruction of numerous fortified positions, apparently abandoned by the NVA early in the artillery attack. Colonel Stockman then ordered the battalion to move toward Con Thien.


With the exception of the Hill 117 battle, contact diminished during the last days of Operation Hickory and the artillery operations to the east. Nevertheless, the Marines found and destroyed numerous well-fortified areas before the operation terminated on 28 May. In addition, they captured or destroyed more than 50 tons of rice and 10 tons of ordnance. Total enemy casualties for the combined Marine/ARVN operation were 789 killed (the equivalent of two NVA battalions), 37 captured, and 187 weapons taken. Of this total 447 were killed by Marines (85 in Beau Charger, 58 in Belt Tight/Hickory, and 304 in Hickory). Allied losses for the operation were by no means small; the Marines lost 142 killed and 896 wounded, while ARVN losses were 22 killed and 122 wounded.

The first large-scale allied entry into the southern half of the DMZ signified that the rules had changed. The area was no longer a guaranteed Communist sanctuary from which they could launch attacks. More immediately, the operation had upset, at least temporarily, the NVA organizational structure in the DMZ. The Marines realized that this initial search and destroy operation would not permanently deny the enemy’s use of the area. Nevertheless, while total friendly control had not been established over the region, the removal of the civilian population from the area, some 11,000 people, now permitted the Marines complete freedom of use of supporting arms.


Operation Prairie IV Ends

At the end of Operation Hickory, all participating forces joined Operation Prairie IV and continued sweeps of “Leatherneck Square” and the area southwest of Con Thien. On 28 May, the 3d Battalion, 4th Marines made heavy contact on Hill 174, approximately four miles southwest of Con Thien. The NVA were in bunkers, similar to the complex encountered on Hill 117. Two Companies, M and L, attacked late in the afternoon, only to be “blown off 174” by a heavy volume of fire from enemy small arms, automatic weapons, 57mm recoilless rifles, and 82mm mortars. Accounting for all personnel took much of the night. Results of this initial engagement were 2 Marines killed and 21 wounded. Known enemy casualties were 4 dead; with another 4 probably killed.

The 3d Battalion, 4th Marines called in artillery throughout the night; the North Vietnamese responded with 82mm mortars. The following day, the 29th, Companies M and I, the latter led by Lieutenant Walter E. Deese’s 1st Platoon, attacked up the hill. Despite being hit by friendly 60mm mortars, the Marines made contact with the NVA defenders around 1600. Enemy resistance remained firm; 5 more Marines died, 33 suffered wounds. This time, however, the Marines managed to hold positions on the western and northern slopes of Hill 174. The crest remained in enemy hands.


On 30 May, I and M Companies attacked again. Despite heavy supporting arms fire and the Marines’ use of flame throwers and 3.5-inch rocket launchers, the enemy retained control of the hill. Another Marine died; 45 were wounded. There were seven confirmed enemy dead. The North Vietnamese, however, decided to give up the contest. Company M reached the crest of Hill 174 on 31 May, meeting no resistance.

Operation Prairie IV, the last of the Prairie series of operations was over. It, like its predecessors, hurt the enemy: 505 died, 8 captured, and 150 weapons seized. Friendly losses were 164 killed and 1,240 wounded.

On 1 June, Operation Cimarron began in the same area and with the same formations. The operation lasted through 2 July, producing only light contact. The Marines discovered and destroyed several large, abandoned, fortified positions in the area southwest of Con Thien and unit sweeps located numerous enemy graves and several supply caches.

While Cimarron progressed, the land clearing project from Con Thien through Gio Linh to the high water mark on the coast reached completion by 1 July. The Marine engineers widened the previously cleared area to 600 meters for the entire 13.5 kilometers of its length. The 11th Engineer Battalion contributed more than 10,000 man hours and 4,500 tractor hours to this hazardous effort.


During the last days of Cimarron a sharp increase in enemy artillery activity, coupled with several small but intense engagements between patrols and dug in NVA units around Con Thien, indicated that the enemy was preparing for renewed offensive operations in the area. There was to be much hole digging and sandbag filling before the summer ended.




(1)     There is no illumination round for the 175mm gun.

(2)     This was the first instance of NVA use of flamethrowers against the Marines.

(3)     “Leatherneck Square was the quadrilateral between Con Thien, Gio Linh, Dong Ha, and Cam Lo.

(4)     At ComUSMACV’s request, CinCPac committed a second SLF to the area on 15 April. The two SLFs were identified as Alpha and Bravo.

(5)     Lam Son was an ancient Vietnamese cultural hero for whom all the 1st ARVN Division operations were named.  LtGen Louis Metzger, comments on draft MS,. [1981].

(6)     At the request of ComUSMACV, CinCPac directed the deployment of BLT ¾, the last element of the Pacific Command reserve, to I Corps.  In a massive 42-plane Air Force and Marine airlift the BLT moved directly from Okinawa to Dong Ha.  The entire lift of the 1,233-man force took exactly 31 hours.

(7)     While the damage to the helicopters was minor, this and subsequent attacks disrupted helicopter operations by preventing normal maintenance. This caused the rotation of squadrons in July and the subsequent abandonment in the fall of Dong Ha as a permanent helicopter base in favor of Quang Tri. LtCol Horace A. Bruce, Comments on draft ms, 14Jul81. (Comment File, MCHC, Washington, D.C.)

(8)     The Ontos, or M50A1, was a lightly armored, tracked vehicle which mounted six 106mm recoilless rifles. Originally intended as an antitank vehicle, the Ontos, because of its mobility, became an all-purpose infantry support weapons system in Vietnam.

(9)     High temperatures reduce helicopter lift capability, hence the inability to evacuate the large quantities of rice without diversion of additional helicopters from other missions.

(10)  The battalion’s movement from the SLF shipping to its inland TAOR was called Operation Belt Tight.

(11)  Operational control of Co.K had passed to Colonel Masterpool’s 2d Battalion, 26th Marines at 1645 on the 25th.