At 04:30 on 21 March, a night patrol from Company B which was operating outside the perimeter reported movement near its ambush site. However no further movement was detected for two hours. At 06:30 the patrol prepared to return to camp. One minute later, explosions were set off in the area as the US base came under heavy attack from enemy 60 mm and 82 mm mortars. Simultaneously, the patrol was attacked by a VC force. Within five minutes, the patrol had been overpowered and all of its men were killed or wounded. The first VC mortar round landed outside a company command post; seconds later another exploded outside battalion headquarters. An estimated 650 mortar rounds fell while the VC advanced towards the perimeter. As they moved closer, machine guns and recoilless rifles joined the attack as the VC prepared to assault the position. Minutes later, the entire perimeter came under attack by waves of VC infantry emerging from the jungle and firing recoilless rifles,
RPG-2 rockets, automatic weapons and small arms. The heaviest attacks were concentrated on the northeastern and southeastern portions of the base. As the VC attack intensified, the three US artillery batteries began to return mortar fire at their VC counterparts. During the first assault, Company B reported that its 1st Platoon positions on the south-eastern perimeter had been penetrated and that a reaction force from the 2/77th Artillery, was needed to reinforce them. Artillery was sent to the perimeter to help repulse the continuing attacks. At 07:00 the first
Forward Air Controller (FAC) arrived to direct airstrikes against the VC. At the same time, two batteries of 105 mm
howitzers located at nearby fire support bases were brought within 100 m of the battalion's perimeter. At 07:11, Company B reported that its 1st Platoon had been overrun and faced by an infantry charge. Airstrikes were called in all along the wood line to the east to ease the pressure on the besieged company. Then the FAC directing these strikes was shot down by automatic weapons fire. At 07:50 the Company B commander requested that the artillery fire
beehive rounds into the southeastern and southern sections of his perimeter. At 07:56 Company B reported that the VC had penetrated the 1st Platoon sector and ammunition was depleted there. Ammunition and 20 men from Company A were sent to assist B Company. At 08:13 the northeastern section of the perimeter was overrun by another infantry charge. At 08:15, elements of Company A which had established an ambush just outside the perimeter the previous night charged into the camp's perimeter and assumed defensive positions, managing to evade the surrounding VC. Company A reported that the VC had penetrated the northern perimeter. Ten minutes later an
M45 Quadmount machine gun located there was hit by RPG-2 rounds and overrun. As the attacking VC reached the weapon and attempted to turn it on the Americans, the gun was blown apart by a round from a 105 mm howitzer crew from their position 75 m away. By 08:40 the Americans on the northeastern, eastern and southeastern perimeter had withdrawn to a secondary defensive line around the artillery. The northern, western and southern defenders were managing to hold despite large numbers of VC who had come within 15 m from the defensive positions, and within hand grenade range of the battalion command post and only 5 m from the battalion aid station. The howitzers, now depressed to almost zero elevation, began firing beehive rounds into the VC at point-blank range. Each round had 8,000 finned steel missiles directed at their target. Airstrikes were brought in within 50 m of their compatriots and supporting artillery pounded areas around the perimeter to stop the VC. When the artillerymen had exhausted their supply of beehive rounds, they began to fire high explosive rounds at point-blank range. By 09:00 the northern, western, and southern sectors of the perimeter were holding despite ongoing VC pressure. The positions on the east had withdrawn inwards, but were still intact. The 3rd Brigade headquarters had already alerted its other units conducting operations to the west. They were the 2/12th Infantry, the 2/22nd Infantry (Mechanized), and the
2nd Battalion, 34th Armor Regiment. When word of the attack reached these forces, they returned immediately to base. The 2/12th Infantry moved from the northwest and the mechanized infantry and armor battalions moved from the southwest until they reached the stream, where they were held up while finding a feasible crossing site, of which there was only one. At 09:00 the relief column from the 2/12th Infantry broke through the VC and linked up with the depleted Company B. With the replenished forces and firepower, the two units were able to counterattack to the east and reestablish the original perimeter. The VC continued attacking, using wounded soldiers who had been bandaged earlier in the same battle. The Americans reported that they were advancing, even though some could not walk and had to be carried into offensive positions by colleagues. Twelve minutes after the first US relief unit arrived, the mechanized infantry and armor column broke through the jungle from the southwest to reinforce the American defenders. With their 90 mm guns firing canister rounds and machine guns raking the VC, they moved into the advancing VC, cutting them down and forcing them to withdraw. By 09:30 the base perimeter had been re-secured and thirty minutes later, helicopters had arrived to evacuate the wounded Americans. By 10:45 the battle was over, except for various armored cars and tanks that pursued the retreating VC, who were also targeted with artillery and air strikes. This continued until noon. == Aftermath ==