The scouts had relatives on both sides of the border. During Operation Khas, the Royal Malaysia Police's Border Scouts recruited indigenous Dayak men from Kalimantan whose family connections stretched across the frontier. These informants reported Indonesian troop movements from inside the jungle, passing intelligence to a Commonwealth network that had learned, from the Battle of Tawau, how costly a surprise could be. Operation Khas ran from September 1964 to July 1966, a quiet, grinding effort to prevent the next attack before it began.
The Battle of Tawau in late 1963 had demonstrated what happened when Indonesian forces crossed the border in strength. Eight soldiers of the 3rd Royal Malay Regiment died at Kalabakan, and though the incursion was eventually defeated, the lesson was clear: the 130-kilometer land border and 162-nautical-mile maritime frontier of the Tawau Division could not be left to conventional garrison tactics alone. Operation Khas was the Commonwealth's response - part of the broader Operation Claret that governed cross-border operations across Sabah and Sarawak. Unlike Claret's occasional offensive raids, Khas focused on defense: screening, blocking, and territorial denial, the patient work of ensuring that nothing crossed the border undetected.
The intelligence network was built on human relationships. Dayak communities in Kalimantan had ties to communities in Sabah, and the Border Scouts exploited these connections to create a web of informants who could report on Indonesian military activity in the jungle. The system was not foolproof - small, dispersed units could slip through - but it made large-scale raids nearly impossible to mount in secret. After the Battle of Plaman Mapu, Indonesian strategy shifted to guerrilla tactics: small skirmishes targeting police stations, military camps, and government infrastructure. Detecting these smaller operations required different skills. The SAS units - Australian, New Zealand, and British 22 SAS - along with the Malaysian Special Service Unit conducted deep reconnaissance patrols, slipping through the forest canopy on foot to monitor trails and river crossings.
By 1965, the Tawau Division hosted an extraordinary concentration of Commonwealth military power. The 10th Gurkha Rifles and the 3rd Royal Malay Regiment provided infantry backbone. The 4th Battalion Royal Australian Regiment and 1st Battalion Royal New Zealand Infantry Regiment brought additional strength. For specialized operations, the roster included the Australian and New Zealand SAS, the British 22 SAS, 40 Commando Royal Marines, No. 2 Special Boat Section, and the Malaysian Special Service Unit. A principal army base established in Tawau in 1963 served as the forward operating hub, supported by a network of police field posts and patrol stations strung along the border. On the maritime side, Royal Australian Navy warships maintained a constant presence in the waters around Sebatik Island.
The system's greatest test came on 28 June 1965. Indonesian commandos from the Commando Operations Corps, based on the Indonesian half of Sebatik Island and reinforced from Nunukan Island, launched a frontal assault on the Commonwealth outpost at Wallace Bay. It appeared to be an attempt to seize the entire Malaysian portion of Sebatik. The frigate HMAS Yarra, on station off Wallace Bay, responded with shore bombardments that drove the attackers back into Indonesian territory. Two more incursions followed on 5 and 10 July, both broken by Yarra's guns. Post-conflict analysis revealed that Indonesia deployed its less-trained North Borneo Liberation Army fighters to harass Commonwealth positions while reserving professional commandos from the Marine Corps and the Army Para-Commando Regiment - the forerunner of Kopassus - for more organized raids. Operation Khas held the line until the Confrontation ended in 1966.
Located at 4.28N, 117.89E in the Tawau Division of eastern Sabah. The operation covered the full 130-km land border with Indonesian North Kalimantan and the maritime approaches through the Celebes Sea. Sebatik Island, divided between Malaysia and Indonesia, is visible south of Tawau. Wallace Bay, site of the June 1965 assault, is on Sebatik's Malaysian coast. Tawau Airport (WBKW) serves as the nearest aviation facility. The dense jungle canopy that defined this border war remains largely intact along the frontier.