- In the direction of the Central Highlands, Vietnamese soldiers pursued the enemy. At noon on March 22, the 64th Regiment of the 320th Division liberated Pui Station and advanced to Cung Son. In Phu Yen, the enemy concentrated on the 924th Security Regiment, the 268th Security Battalion and two companies to launch a fierce counterattack on the Vietnamese blocking line west of Hon Ken.
- On the same day, the 271st Regiment of the main force opened fire and attacked targets in Gia Nghia Town. Local troops and guerrillas of Khiem Duc District moved in to support the main force to take over Gia Nghia Town, fighting the enemy fleeing on Highway 8 in the Hang No and Kinh Da areas. Local troops of Lam Dong Province ambushed and captured nearly 200 of them. Only a few escaped into the forest and ran towards the Dong Nai River.
- In the direction of Thua Thien-Hue, the enemy organised a counterattack to clear Highway 1 but failed, falling into isolation and starting to panic. Although Commander of Region 1 Ngo Quang Truong was determined to keep Hue, Da Nang and Chu Lai, President Nguyen Van Thieu still ordered the withdrawal of troops from Hue.
On March 22, 1975, the enemy’s forces and war vehicles began to withdraw from Hue city in 3 directions: By sea through Thuan An estuary to Da Nang; Withdraw to defend the Cu Lai area (6km south of Thuan An) and withdraw to Da Nang via the Tu Hien estuary.
- On the same day, closely following the developments on the battlefield, General Vo Nguyen Giap - Secretary of the Central Military Commission - urgently sent a telegram to Major General Nguyen Huu An - Commander of the 2nd Corps, requesting “The Corps to immediately dispatch forces to block the Thuan estuary”.
The 325th Division advanced to cut Route 1 from Bai Son to Bach Ma, controlling a 4km stretch from Bach Thach to Rang Bo, destroying the enemy’s reinforced checkpoints; defeating the raids of the 1st Division, the 258th Marine Brigade and the 15th Special Forces Group of the Republic of Vietnam. By 10 o'clock, the Hue-Da Nang road was completely cut off. Thousands of enemy vehicles from Hue intending to retreat to Da Nang were stuck and had to return to Hue.
At noon on March 22, 1975, the 2nd Corps Command held a meeting and determined that the best opportunity to destroy and disintegrate the enemy had come and that they were determined to quickly liberate Hue and develop to the south; agreed on a combat plan to coordinate with the Tri-Thien Military Region forces to liberate Hue and assigned the following tasks to the units.
On the evening of March 22, 1975, the forces of the 325th Division continued to develop and attack the enemy in two directions: Mui Ne, Luong Dien and Hill 363 expanding the cut-off road from 4km to nearly 10km.
That same night, the 18th Regiment of the 325th Division attacked from behind and destroyed the Phu Loc sub-region, occupied Mui Ne and Phuoc Tuong passes, and sent forces to block the Tu Hien Gate. The 101st Regiment attacked the Luong Dien Base - a large enemy base occupied by the 15th Special Forces Group and several artillery units.
On the same day, the Tri-Thien Military Region attacked and broke the enemy’s defence line in My Chanh, forcing the enemy to retreat to defend the Bo River defence line. Our forces surrounded Hue City.
On the night of March 22, 1975, the 324th Division advanced eastward, attacked the enemy in Phu Bai, used a regiment to break through Tam Giang to attack the enemy in Ke Sung, Cu Lai, and broke the enemy's plot to withdraw to Tu Hien estuary and the southern bank of Thuan An estuary. The 2nd Regiment followed the western bank to break through Tam Giang and advanced eastward to Hue.
- From March 22 to 24, 1975, on the northern flank of Thua Thien-Hue, the local troops of the province with the 7th Battalion of the 203rd Tank Brigade of the 2nd Corps coordinated to attack Thanh Huong, Dai Loc, Huong Dien District, then crossed the My Chanh River to attack Pho Trach, Luong Mai.
On the enemy side, on the evening of March 22, 1975, facing a strong attack from all directions, the Forward Command of the 1st Corps of the Republic of Vietnam fled to Da Nang by helicopter and ordered the remaining forces to organise a withdrawal from Hue.
- Promoting the victory of the Central Highlands campaign, the 12th Regiment of the 3rd Division from the Cay Rui checkpoint cluster (south of An Khe Pass) marched through the forest to the west, marching and organising the battle. At dawn on March 22, 1975, the regiment opened fire to capture the high points on the outskirts of An Khe Town.
