Battle of Sungei Koemba The Battle of Sungei Koemba ( 27 May – 12 June 1965 ) took place during the Indonesia – Malaysia confrontation . Involving Australian and Indonesian troops , the battle consisted of a series of ambushes launched by the 3rd Battalion , Royal Australian Regiment ( 3 RAR ) , along the Sungei Koemba river in Kalimantan ( Indonesian Borneo ) . The ambushes were part of the wider Operation Claret which involved cross - border operations by British - Commonwealth units from bases in Sarawak , penetrating up to into Indonesian territory with the aim of disrupting the movement and resupply of Indonesian forces and to keep them off balance . The first ambush was conducted by two platoon s from B Company on 27 May 1965 and resulted in significant Indonesian casualties , for no loss to the Australians . The second ambush was conducted a fortnight later and was set a little further downstream from the last one , this time by a platoon from C Company , occurring on 12 June 1965 and again resulting in heavy Indonesian casualties for no loss to the Australians . Background . Military situation . Following Malayan independence from Britain in 1957 , proposals to federate the states of Malaya , Sabah , Sarawak , Brunei , and Singapore led to tensions with Indonesia . In late - 1962 the Indonesian president , Sukarno , had begun military operations in an attempt to destabilise the new state , including an attempt to seize power in the independent enclave of Brunei in December . Following the Federation of Malaysia in 1963 , hostilities grew with military activity increasing along the Indonesian side of the border in Borneo , as small parties of armed men began infiltrating Malaysian territory on propaganda and sabotage missions . Carried out by Indonesian irregular " volunteers " , these operations continued throughout 1963 . However , by 1964 Indonesian regular army ( TNI ) units had also become involved . Although not initially agreeing to send troops to Borneo in the opening stages of the Indonesia - Malaysia Confrontation , the Australian government did allow its forces stationed in Malaysia as part of the Far East Strategic Reserve ( FESR ) to be used to protect Peninsular Malaysia from Indonesian attack . 3 RAR , which was based at Camp Terendak in Malacca , was subsequently used to mop up two small airborne and seaborne landings near Labis and Pontian in September and October 1964 . These incursions suggested that a major escalation in the conflict was imminent , and in January 1965 the government conceded to British and Malaysian requests , subsequently agreeing to deploy an infantry battalion to Borneo , in addition to a battery of artillery , an engineer construction squadron , and a squadron from the Special Air Service Regiment . During the early phases , British and Malaysian troops had attempted only to control the border , and to protect population centres . However , by the time the Australian battalion deployed the British had decided on more aggressive action , crossing borders to obtain information and forcing the Indonesians to remain on the defensive , under the codename Operation Claret . The fighting took place in mountainous , jungle - clad terrain , and a debilitating climate , with operations characterised by the extensive use of company bases sited along the border , cross - border operations , the use of helicopters for troop movement and resupply , and the role of human and signals intelligence to determine Indonesian movements and intentions . Prelude . Opposing forces . As part of these operations , British - Commonwealth reconnaissance and special forces patrols frequently crossed the border into the Kalimantan in order to detect Indonesian forces about to enter Sarawak . Initially penetration was limited to , while later it was extended to , and yet again to . Conventional forces were then tasked to act on this information to ambush or otherwise attack the Indonesians . Uncertain of where British - Commonwealth forces might strike next , the Indonesians were increasingly forced to devote their resources to protecting their own positions , reducing their ability to conduct offensive operations , although these continued on a much reduced scale . Given the sensitivity of Claret operations and the potential consequences if they were exposed they were controlled at the highest level , and were highly classified at the time , with the participants sworn to secrecy . When casualties were suffered they were reported as having occurred within Malaysian territory . 3 RAR formally relieved a British Army battalion , the 1 / 7th Gurkhas , in the Bau area of Sarawak on 22 March 1965 , although they had mounted a number of familiarisation patrols inside Malaysian territory over the proceeding weeks . Joining the West Brigade , the Australians were initially deployed in a series of company bases along the border , guarding the approaches to the capital Kuching just away . Commanded by Lieutenant Colonel Bruce McDonald , the battalion was deployed with three of its four rifle companies forward at Stass ( A Company ) , Bukit Knuckle ( B Company ) and Serikin ( C Company ) in order to cover the border areas , with the fourth company ( D Company ) remaining in reserve at Bau along with Battalion Headquarters . On average , each company operated on a frontage of around . In support in West Brigade was the British 4th Light Regiment , equipped with L5 pack howitizer s and medium guns . Included were the guns of 102nd Field Battery , Royal Australian Artillery , which had recently been deployed to West Sarawak . Opposing the Australians were a number of Indonesian units , including elements of the Resimen Para Komando Angkatan Darat ( RPKAD ) and the Diponegoro Division , normally based in KODAM 7 in central Java . These units were among the best in the TNI . In April 1965 two Indonesian battalion combat teams from the 5th Brigade were deployed in the 3 RAR area of operations , designated ' H ' BTP and ' J ' BTP , while a third battalion , ' I ' BTP , was concentrated further to the east ; in total 3 , 050 men under the overall command of Colonel Sujono . These units were supported by at least two detachments of artillery , equipped with anti - aircraft machine - guns and mortars . Regardless , by late April the Australians began their first cross - border reconnaissance patrols . Battle . First ambush , 27 May 1965 . The first Australian fighting patrol into Kalimantan began on 24 May with two platoon s , 5 and 11 Platoon , from B Company and a forward observation party , departing the company base at Bukit Knuckle under the command of Major William Broderick . The patrol — designated Operation Article — involved an ambush patrol along the bank of the Sungei Koemba river . After several days of careful and laborious movement through the thick jungle Broderick established a patrol base on the high ground overlooking the river on 26 May and sent forward a small reconnaissance party of three men with Lieutenant Patrick Beale . The forward element subsequently detected a party of Indonesians in a re - entrant below , talking loudly and firing random shots , seemingly unaware of the proximity of the Australians and unconcerned with basic notions of security . The following morning Broderick moved the company down the spur line in order to establish a firm base , while Beale moved 5 Platoon forward . Four 7 . 62 mm L4A4 Bren light machine - guns were incorporated into the patrol . The Australians encountered a track , beyond which lay the river , while to the north across a shallow creek , movement of the Indonesians could still be heard . The presence of the Indonesians so close to the Australian position made the chances of detection too great and as such no more troops were brought forward . Instead Beale deployed his platoon into two positions , one covering the track with two Brens in order to secure it from the Indonesians in the re - entrant , as well as another position on a bend in the river . Only the sentry on the right - hand flank , Private Lawrence Jackson , could see around the bend , which narrowed to just at that point . At 11 : 32 am , after occupying the position for only 40 minutes , motors were heard approaching along the river , with two motor boats coming into view . Each vessel contained five armed and uniformed Indonesian soldiers , including one fair haired European , who was later identified as a Dutch mercenary . The Australians had not been detected and allowed the boats to draw closer before the ambush was sprung . With the boats just away they opened fire , raking them with automatic fire which emptied the boats of their occupants . The first boat sank and the second drifted down stream . Two Indonesians were observed swimming for the far bank and were subsequently shot , with the other eight also killed . Unknown to the Australians , however , two more boats had been following the first two , and as the third boat rounded the bend in the river Private Jackson engaged the Indonesians , killing all five occupants from a range of just . The fourth vessel subsequently pulled quickly to the shore out of sight of the remainder of the Australians , with Jackson engaging it with two grenades and small arms fire before his weapon jammed . The action had lasted just two minutes to this point , yet already a party of approximately 10 Indonesians across the river began to engage the Australians with heavy automatic fire , although it was largely inaccurate . Beale ordered a withdrawal to link up with the rest of B Company , with the ambush party subsequently rejoining the rest of 5 Platoon while 11 Platoon covered their withdrawal . The forward observation officer subsequently called in a defensive artillery fire mission onto the abandoned position , reducing the volume of Indonesian fire and allowing the Australians to break contact . Shortly after an Indonesian mortar began to fire , dropping rounds into the jungle towards Siding , away from B Company ' s escape route . Elements of D Company and Support Company had been deployed so as to support the withdrawal , and the patrol subsequently recrossed the border into Sarawak without further incident , returning to Bukit Knuckle later that evening . No Australian casualties were incurred and at least 15 Indonesians were believed to have been killed . Later that night an Indonesian radio broadcast announced that 23 Indonesian military personnel had been accidentally killed during a training exercise . Jackson was subsequently awarded the Military Medal for his " complete disregard for his own safety , [ which ] prevented the Indonesians from landing on the near bank and attacking the other members of the ambush . He contributed much to the overwhelming success of the engagement " ; while Beale received the Military Cross for " his personal bravery , inspiring leadership , judgment and skill " . Further Claret operations followed in quick succession , making June the most intensive month of the Australian battalion ' s tour in Borneo , and its most successful . Second ambush , 12 June 1965 . On 10 June a patrol — designated Operation Faun Fare — consisting of 7 Platoon , C Company under Lieutenant Robert Guest , accompanied the company commander Major Ivor Hodgkinson , the Intelligence Officer and a fire control party , left the company base at Serikin to mount an ambush on the Sungei Koemba river . The site of the ambush was to be a little further downstream from the successful action the previous month , being more towards the Indonesian positions at Siding . The Australian patrol occupied its intended ambush position early the next morning and proceeded to wait . During the day two boats occupied by civilians were observed and allowed to pass unhindered , as were three more the next morning . At 10 : 45 am on 12 June Private Haines , a sentry on the left hand flank , warned of the approach of an Indonesian foot patrol along the river bank . The Australians had sited the ambush to engage targets on the river and were initially at a disadvantage . Ten minutes after the Indonesians were first seen , Private Sneddon , on the extreme left , engaged a group of six Indonesians with a long burst of machine - gun fire , killing two instantly and a third as he ran towards him . Haines subsequently killed a fourth , while a fifth Indonesian continued past him , followed by five others , who then engaged the Australians . The Indonesian patrol continued to advance , taking them towards the rear of the Australian positions . Hodgkinson worked his way around to the left towards the Indonesian line of approach , subsequently engaging and killing two more , and wounding a third . Guest gathered the right hand elements of 7 Platoon , hooking around Hodgkinson and counter - attacking the remaining Indonesians , killing the previously wounded soldier and one other . Yet another wounded Indonesian was observed to crawl away while the tenth proceeded to run off unharmed back in the direction from which the patrol had come . Within twenty minutes the contact was over and the Australians proceeded to collect the discarded Indonesian weapons and equipment , including a Browning Automatic Rifle , three MI rifles and 200 rounds of ammunition . Dressed in US steel helmets , green shirts and blue and khaki shorts , the Indonesian soldiers were subsequently identified as members of 440 Battalion . The Australians then withdrew , calling in a defensive fire artillery mission onto the abandoned ambush position in order to allow them to break contact . Later , Indonesian small arms fire was heard to emanate from the same area and a further nine rounds were called in to bombard the site . The patrol harboured for the night , recrossing the border without incident the following day and returning to Serikin . The Australians suffered no casualties , while eight Indonesians were killed and one was seriously wounded . For his leadership of C Company throughout 3 RAR ' s deployment , which " [ brought ] out those highest qualities expected of professional soldiers " , Hodgkinson was appointed Member of the Order of the British Empire on 24 May 1966 . As a consequence , the Indonesians planned to increase their activity against the Gumbang , Tringgus and Bukit Knuckle areas , while additional forces were also subsequently redeployed against Serian . In response , Australian reconnaissance patrols were increased in order to detect movement into Sarawak , and these would later result in further fighting . Perhaps in retailiation , Indonesian mortars subsequently targeted a number of Australian positions along the border , firing 13 rounds , while a further 25 rounds were fired at 11 : 00 am . There were no casualties . Aftermath . Assessment . In addition to inflicting significant casualties on Indonesian forces , the successful Australian ambushes on the Sungei Koemba , and later at Kindau , in May and June allowed 3 RAR to dominate the border area , while also providing early warning of Indonesian incursions into Sarawak . Following these actions Major General George Lea , the British Director of Operations , ordered a short pause in offensive operations in order to observe the effects . Indonesian mortar attacks on company bases in the 3 RAR area of operation , which had been heavy throughout May and June , ceased soon afterwards . Following the resumption of Claret operations the Australian battalion later followed this up with another profitable mission at Babang on 12 July , contributing to the wider success of the British - Commonwealth forces in slowly asserting control on the war . Overall , Operation Claret was largely successful in gaining the initiative , inflicting significant casualties on the Indonesians and keeping them on the defensive , before being suspended late in the war . Generally British Commonwealth units on their first tour in Borneo were not allowed to undertake such audacious operations however , and consequently , although highly successful the actions of 3 RAR in their first and only tour may not have been representative of those by more experienced Gurkha and British battalions . Denied during the war , these incursions were only publicly disclosed by Britain in 1974 , while the Australian government did not officially acknowledge its involvement until 1996 . 3 RAR carried out 32 Claret operations in total , including 12 reconnaissance patrols and 20 ambushes or fighting patrols , although the majority never resulted in contact . In contrast , Indonesian activity was usually small - scale and aimed to challenge incursions rather than to attack them . Subsequent operations . 3 RAR completed its tour in August 1965 and returned to Camp Terendak , being relieved in West Brigade by the 2 / 10th Gurkhas . During its four months in Borneo the Australian battalion had suffered three men killed and five wounded , the bulk of which occurred during two separate land mine incidents . The 2 / 10th Gurkhas subsequently fought a number of heavy engagements against the Indonesians , including an action at Bau on 21 November 1965 , during which 24 Indonesians were killed for the loss of three Gurkhas . One of the Gurkhas , Lance Corporal Rambahadur Limbu , was later awarded the Victoria Cross ; the only such decoration of the conflict . Meanwhile , the 4th Battalion , Royal Australian Regiment ( 4 RAR ) arrived in Malaysia in September 1965 to replace 3 RAR in the FESR , with the battalion returning to Australia in October . After a period of training the new battalion deployed to Sarawak in April 1966 where it also operated from a series of company bases around Bau . However , by this time the war was winding down as peace negotiations had begun between Malaysia and Indonesia , and although 4 RAR was involved in a number of contacts , its tour was less eventful . Notes . Footnotes Citations References . Online sources