On the afternoon of 11 March ARVN General Lê Nguyên Khang ordered the 345th Armored Squadron to move out from Bau Don to relieve the military zone of Dầu Tiếng, but they were defeated by the PAVN 16th Infantry Regiment at Suoi Ong Hung, and forced to retreat to their base. At the same time, ARVN artillery units at Bau Don and Rung Nan were subdued by elements of the 9th Infantry Division, so they were unable to return fire. By 13 March the PAVN was in complete control of the Dầu Tiếng military zone. After three hours of fighting, the PAVN 9th Infantry Division also captured ARVN positions at Vuon Chuoi, Nga ba Sac, Cau Tau and Ben Cui. The ARVN 3rd Brigade had planned to retake Dầu Tiếng using elements of the 5th Division, but Thiệu ordered them to pull back and defend Truong Mit, Bau Don and Tây Ninh instead.