The first Australian battalion, 3 RAR, arrived in Borneo in March 1965 and served in Sarawak until the end of July. During this time the battalion conducted extensive operations on both sides of the border, were engaged in four major contacts with Indonesian units, and twice suffered casualties from land mines. Its replacement, the 28th Brigade, 4 RAR, also served in Sarawak - from April until August 1966. Although it had a less active tour, the 28th Brigade also operated on the Indonesian side of the border and was involved in clashes with Indonesian regulars. Altogether, two squadrons of the Special Air Service, a troop of the Royal Australian Signals , several artillery batteries and parties of the Royal Australian Engineers were involved in Borneo, in addition to the two infantry battalions. Ships of the Royal Australian Navy served in the surrounding waters and several RAAF squadrons were also involved in Confrontation.