Operation Hump was a search and destroy operation initiated on 8 November 1965 by the 173rd Airborne Brigade, in an area about 17.5 miles (28.2 km) north of Bien Hoa. The 1st Battalion, Royal Australian Regiment deployed south of the Dong Nai River while the 1st Battalion, 503rd Infantry, conducted a helicopter assault on an LZ northwest of the Dong Nai and Song Be Rivers. The objective was to drive out Viet Cong fighters who had taken position in several key hills.