 By the second half of 1967 the Viet Cong seemed to have melted away in Phuoc Tuy province , abandoning many of their bunker systems and avoiding the main roads and towns . The Battle of Long Tan and Operation Bribie had weakened the communist forces in the province , while further operations had restricted their movement and logistics . This prompted the commander of the 1st Australian Task Force ( 1 ATF ) — Brigadier Stuart Graham — to speculate that the Viet Cong may have fled to the border , perhaps leaving the province altogether . Graham reasoned that a succession of operations in the south @-@ east of the province and the completion of the barrier minefield at Dat Do meant that no single , sizable threat remained to the populated areas of Phuoc Tuy . 
