On 28 May 1965 a Section of 1 Div Pro Coy (1st Division Provost Company) arrived in South Vietnam. This section was increased in strength and became AFV Pro Unit (Australian Force Vietnam Provost Unit), with a maximum strength of 4 Officers and 65 ORs from Australia, with RAAF Service Police, RNZ Provosts (Royal New Zealand Provosts), US Military Police and Regimental Police from various units attached. The Army Special Investigation Branch (SIB) served in Vietnam as well, detecting and investigating serious crime among Australian troops.