 The 1st Australian Task Force (1 ATF) began arriving in Phước Tuy Province of South Vietnam between April and June 1966.Following the establishment of its base at Nui Dat in Operation Hardihood, standing patrols were established outside the base in the evening and clearing patrols sent out every morning and evening along the perimeter.Daily platoon patrols and ambushes were initially conducted out to Line Alpha (), which was the range of the Viet Cong (VC) mortars, but were later extended out to Line Bravo () to counter the threat from artillery.