In May 1965, the VC 271st Regiment (part of the Viet Cong 9th Division) moved into northern Quảng Ngãi from the neighbouring province of Quảng Nam. The VC 271st Regiment had three battalions (the 40th, 60th and 90th Battalions), and was placed under the command of Le Huu Tru. In northern Quảng Ngãi, the 271st Regiment joined the 45th Independent Battalion and the 83rd Local Force Battalion. On the other side, South Vietnamese military units in Quảng Ngãi Province formed part of the ARVN 1st Brigade, I Corps Tactical Zone, commanded by General Nguyễn Chánh Thi. In Quảng Ngãi the main ARVN force included the 51st Infantry Regiment (part of the 25th Infantry Division), Marine Corps Task Force B, 1st and 3rd Marine Battalions, the 37th and 39th Ranger Battalion, the 5th Airborne Battalion, and two artillery battalions equipped with 105mm artillery guns.