(General Hieu, 3rd Corps Deputy Commander/Operations, was the behind-the-scenes player who designed and executed this military operation. Tin Nguyen)
(April 27-May 2, 1974)
The two major thrusts of the new ARVN offensive were both directed against the veteran 5th NVA Division, which during January began moving from Tay Ninh toward Dinh Tuong Province. Time was of the essence, for if the 5th was able to occupy the Communists' Tri Phap base it would be extremely difficult to root out. Moreover, its presence in Dinh Tuong would place Route 4, Saigon's vital link to the delta, in grave jeopardy.
During the second week of February elements of the 7th and 9th ARVN Divisions attacked the Tri Phap from the south and east. Taken by surprise, the Communists fell back with heavy losses in men, ammunition, and supplies. For the rest of February and through the entire month of March, fighting spread across Dinh Tuong and Kien Tuong Provinces, but the focus of the campaign remained in the Tri Phap where government forces continued to score heavily. Hoping to divert ARVN's attention while reinforcements were deployed to the battle area, COSVN staged widespread attacks on isolated positions and stepped up its terror campaign in the delta. Twenty-three children died in a mortar attack on a school in Cai Lay. Nine more people were killed and sixteen wounded when terrorists hurled grenades into a religious gathering in Bac Lieu.
Such outrages failed to deflect the government's assault on the Tri Phap. After six weeks of fighting the operation had netted more than 1,000 enemy killed, 5,000 tons of food, over 600 weapons, eight tons of ammunition, and a large quantity of other military equipment. Looking to consolidate their victory, ARVN engineers began construction of fortified positions that were soon occupied by Regional Force battalions. At the end of April the NVA overran two of the RF outposts but were quickly driven back by regular government troops. By the first week of May the army of South Vietnam was in firm control of the Tri Phap. Communist forces in the area had been badly mauled, and the soldiers of the 5th NVA Division had been denied the crucial base area.
The division itself, however, now located in the Parrot's Beak salient along the Cambodian border west of Saigon, remained a serious threat to the Tay Ninh-Saigon corridor. That threat had materialized on March 27 when units of the 5th Division attacked and invested the ARVN base at Duc Hue. As April wore on, and Communist forays out of Svay Rieng Province in Cambodia increased, III Corps commander Lieutenant General Pham Quoc Thuan collected twenty South Vietnamese maneuver battalions around the Parrot's Beak, determined to neutralize the North Vietnamese before the onset of the heavy rains of the summer monsoon.
On April 27 General Thuan sent the 49th Infantry Regiment and the 7th Ranger Group through the swamp lands around Duc Hue toward the Cambodian border as South Vietnamese warplanes attacked known and suspected base areas of the 5th Division. Simultaneously, two RF battalions pushed north from Moc Hoa, establishing blocking positions on the southwestern edge of the 5th Division's logistical base and assembly area. On April 28, with eleven ARVN battalions already in the field mounting a variety of operations preliminary to the major assault Thuan had readied for the following day, the 275th NVA Regiment and 25th Sapper Battalion launched a furious assault on Long Khot District Town just inside the border of Kien Tuong Province. Whether planned in advance or a reaction to the initial ARVN maneuvers, the attack on Long Khot did nothing to change Thuan's plans. On the morning of April 29 three South Vietnamese armored columns plunged across the Cambodian frontier west of Go Dau Ha, driving straight toward the Communist 5th Division headquarters.
The threat to the division's base had become so critical that the NVA was compelled to retrieve units fighting at Long Khot to defend Communist forces and logistical installations in the path of the ARVN advance. Meanwhile, South Vietnamese infantry and armored cavalry units based at Moc Hoa crossed into the Elephant's Foot, threatening to isolate the retreating 275th Regiment. As the armored columns continued to drive forward, penetrating as much as sixteen kilometers into Cambodian territory before wheeling south toward Hau Nghia Province, and government helicopters ferried troops into surprise attacks on enemy positions, other ARVN units conducted sweep operations between Duc Hue and Go Dau Ha. By May 10, when the last ARVN units turned for home, Communist communications and logistics in the area had been severely disrupted. The NVA had suffered more than 1,200 men killed, 65 captured, and hundreds of weapons lost. On the other hand, the speed, secrecy, and coordination of the multifaceted operation had limited ARVN KIA to fewer than 100.
Samuel Lipsman and Stephen Weiss