In 1967, 2 and 7 RAR assumed responsibility in Phuoc Tuy from their predecessors and continued the extensive patrolling, and cordon and searches characteristic of this conflict. In August 1967, 7 RAR fought elements of the Viet Cong 3rd Battalion, 274th Regiment in the largely unheralded Battle of Suoi Chau Pha, where extensive artillery support again proved decisive. A third infantry battalion arrived in December 1967 as part of a significant expansion of 1 ATF. By the time of the Tet Offensive in 1968, 1 and 3 RAR were serving in theatre. During actions at Fire Support Base (FSB) Coral by 1 RAR and at FSB Balmoral by 3 RAR in May and June 1968, later known as the Battle of Coral–Balmoral, these two battalions of the regiment would fight battles with conventional attributes not seen since Kapyong. In June 1969, an infantry company from 5 RAR, then on its second tour, and supported by a troop of tanks and another of APCs fought a significant combined arms action against a battalion-sized force of North Vietnamese regulars and Viet Cong local force troops during the Battle of Binh Ba.