On 23 November 1948, Lin Biao's army gained control of Shanhaiguan and severed the Beijing-Tianjin railroad.
Zhangjiakou Nie Rongzhen deployed the Second Army (commanded by
Yang Dezhi) and the Third Army (commanded by
Yang Chengwu) to attack
Zhangjiakou. On 29 November 1948, the People's Liberation Army launched an assault on Zhangjiakou. Fu Zuoyi ordered the Nationalist 35th Corps in Beiping relieve the city. On 2 December, the PLA Second Field Army began to approach
Zhuolu. The PLA Fourth Field Army captured
Miyun on 5 December and advanced toward Huailai. Meanwhile, the Second Field Army advanced to the south of Zhuolu. As Beiping was at risk of being encircled, Fu recalled both the 35th Army and the 104th Army from Zhangjiakou to return and support the defense of Beiping before being "surrounded and destroyed" by the PLA.
Xinbao'an The Third Army trapped the 35th Corps at Xinbao'an. Nationalist reinforcements from Beiping were intercepted by the Communist forces and were unable to reach the city. Fu Zuoyi ordered the Nationalist forces to stay in place, believing that other Communists forces were far away. In fact, most of Lin Biao's army had already reached its planned positions on 12 December. The Communists had surrounded and isolated the major strong points of the Nationalist defenses. The Communists began secret talks with Fu in an effort to convince him to surrender. His daughter
Fu Dong, an underground member of the Communist party, facilitated the talks. On 19 December, the talks reached impasse. The PLA then launched an assault against the city on 21 December and captured the city the next evening. Commander of the 35th Corps
Guo Jingyun committed suicide as the Communist forces broke into the city, and remaining Nationalist forces were destroyed as they attempted to retreat back to Zhangjiakou.
Tianjin After capturing both Zhangjiakou and Xinbao'an, the PLA began to amass troops around the Tianjin area beginning on 2 January 1949. Immediately after the conclusion of
Huaihai campaign in the south, the PLA launched the final assault on Tianjin on 14 January. After 29 hours of fighting, the Nationalist 62nd Army and 86th Army and a total of 130,000 men in ten divisions were either killed or captured, including the Nationalist commander
Chen Changjie. Remainder of the Nationalist troops from the 17th Army Group and the 87th Army that participated in the battle retreated south on 17 January by sea. ==Surrender of Beiping==