On the western wing of Hue front, the 4th Infantry Regiment of Military Region 5 pursued the enemy down to the Sinh crossroads. In the south wing, the 3rd Regiment (324th Division) collaborated with tanks to capture Mang Ca. The encirclement by the southern forces of Thua Thien Hue Province formed two directions, tightly encircling the enemy in Hue and Thuan An port.
By noon on March 25, 1975, all forces of the 2nd Corps and Tri-Thien Military Region advanced towards Hue from various directions, encircling the city on all sides and swiftly entering the city centre.
From the south and north of Hue, the vanguard of the 8th Battalion was led by local militia, simultaneously with the 101st Regiment of the 325th Division, supported by the people and local forces using motorbikes and three-wheeled vehicles to advance directly into the city centre.
On March 25, 1975, Hue City was liberated.
That evening, on the outskirts of the city, the Hue City Party Committee held a meeting to decide on mobilising the masses to rise up in coordination with armed forces to liberate the entire province.
Also on March 25, the districts of Phu Vang, Quang Dien, Phu Loc, and Huong Thuy were all liberated.
In Quang Nam Province, on March 25, 1975, the 38th Regiment of the 2nd Division, supported by tanks, attacked the Tuan Duong Base, and the enemy quickly surrendered.
At the same time, the 70th and 72nd Battalions pursued the remnants of the enemy in the eastern region and Tam Ky Town.
The V20 and V14 Companies of Tam Ky District closely coordinated with the main force to pursue the enemy at Chu Lai Airport and Ky Ha Port, capturing and securing war spoils.
In Que Son, on March 25, 1975, the enemy in the central district headquarters began to panic, and many local military and militia units disbanded. The US-backed Saigon administration largely abandoned their posts and sought escape routes.
The 51st Regiment of the 3rd Division of the Republic of Vietnam at Dong Mong, Da Ham, and Cam Doi started to retreat but still laid dense anti-tank mines along Road 105 to prevent pursuit.
At 7:00 AM on March 25, 1975, the military and people of Duc Pho and Mo Duc districts surrounded and captured two security battalions and the logistics unit of the 4th Regiment of the Republic of Vietnam, liberating the two districts.
Simultaneously, the 81st Battalion and the 95th Company, along with the people of Binh Son, took control of the district capital and town of Chau Ô. The enemy's 2nd Infantry Division, the 11th Special Forces Brigade, and various artillery and armoured units were defeated and disbanded, and Quang Ngai Province was completely liberated.
Meanwhile, in Binh Dinh, at 5:00 AM on March 25, 1975, the 2nd and 141st Regiments entered and occupied the attack positions waiting for orders to attack Lai Nghi—a fortified base on Highway 19 held by the 22nd Division of the Republic of Vietnam. The enemy detected and sent forces to counterattack. The battle here was intense.
- In Military Region 8, on March 25, 1975, the 8th Division attacked and destroyed the Kenh 1 canal outpost in Thanh My and Nga Sau. The 283rd Special Forces Battalion of the Military Region destroyed two outposts in the northeast of Nga Sau and the Hau My crossroads, opening up a large, continuous liberated area between the districts of Cai Be (My Tho), My An, Kien Van (Sa Dec), and Region 4 (Kien Tuong).
Local forces in Cai Be District coordinated with the main force to support guerrillas in destroying and forcing the retreat of four outposts on Highway 20 and four others in the south and north of Highway 4.
On Highway 12, the 3rd Regiment of the 8th Division successively destroyed the Ba Thua outpost in Tan Ninh Commune, two outposts in the Khang Chien Canal, and the Lo Ren crossroads in My Hanh Trung Commune, along with engineering forces cutting off the road at many points.
On March 25, the Politburo affirmed that “a major strategic opportunity has arrived. Never has it been more favourable than now, from the past 20 years. The revolution in the South has made significant leaps, but this is a decisive leap.”
They resolved to seize the strategic opportunity, utilise time to the fullest, concentrate the country's efforts, quickly mobilise forces, weapons, techniques, and materials towards the main direction, act swiftly and boldly to catch the enemy off guard and liberate Saigon before the rainy season.
The Politburo and the Central Military Commission also approved the plan to liberate Da Nang and decided to establish the Da Nang Front Command. Comrade Le Trong Tan, Deputy Chief of the General Staff, was appointed Commander, and Comrade Chu Huy Man, Commander of Military Region 5, was appointed Political Commissar and Party Secretary.
The Politburo also decided to establish the 3rd Corps, comprising units that had fought in the Central Highlands, with Comrade Vu Lang appointed Commander, and Comrade Dang Vu Hiep as Political Commissar.
On the same day, the Politburo issued Resolution No. 241-NQ/TW to establish the Southern Aid Council, chaired by Comrade Pham Van Dong, Politburo member and Prime Minister. The Council's tasks included:
1 - Mobilising and transporting human and material resources from the large rear base in the North to support the battlefield.
2- Handling issues related to taking over newly liberated areas in the South.
3 - Directing and coordinating sectors and localities to implement the plan to aid the South.
On March 25, 1975, the Central Military Commission and the General Staff instructed Military Region 5 and the 2nd Corps to “act boldly and unexpectedly, catching the enemy off guard, concentrating forces to destroy the enemy's large forces in Da Nang to achieve a decisive victory in this decisive battle, create conditions for the next strategic battle.”
On the same day, the General Staff deployed a large part of the 1st Corps to participate in the campaign to liberate Saigon. The 308th Division was tasked with strategic reserve duties for the Ministry and defending the North.
At night on March 25, 1975, the Military Region 5 Command decided to liberate Da Nang quickly. Meanwhile, in Tam Ky and Quang Ngai, soldiers of the 2nd Division, the 52nd Brigade, the 572nd Artillery, the 573rd Anti-Aircraft, and the 574th Armoured Regiments rapidly advanced towards Da Nang. The Quang Da Provincial Party Committee, led by Comrade Tran Thuan, mobilised the people throughout the province to rise up and coordinate with the main force to liberate their homeland.
At 18:00 on March 25, 1975, the Central Military Commission sent a telegram to the Military Region Party Committee, Comrades Tran Van Tra and Pham Hung, emphasising: “A major strategic opportunity has arrived. We must seize time to the fullest, concentrate forces on the main direction, act boldly and unexpectedly, and complete as soon as possible the strategic resolve set by the Politburo. Ensure that all levels are well-informed, concentrate forces on the main objectives."
