With Dau Giay and all the main roads under PAVN control, Xuân Lộc was completely isolated, the 18th Division was cut off from reinforcements and surrounded by the PAVN 4th Army Corps. On 19 April the Joint General Staff ordered Đảo to evacuate the 18th Division and other support units from Xuân Lộc to a new defensive line formed east of Bien Hoa at the town of Trảng Bom which was defended by the remnants of the Division, the 468th Marine Brigade and the reconstituted 258th Marine Brigade. On 20 April under the cover of heavy rain, South Vietnamese soldiers and civilians began pulling out from Xuân Lộc, in a convoy of about 200 military vehicles. On 21 April Xuân Lộc was completely abandoned, with the ARVN 1st Airborne Brigade being the last unit to be evacuated from the area. At 04:00 on 21 April the 3rd Battalion, 1st Airborne Brigade was completely destroyed by the PAVN at the hamlet of Suoi Ca. By the end of the day Xuân Lộc was under North Vietnamese control and the gateway to Saigon was open.