text: 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 10 , 000 yards ( 9 , 100 m ) 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 platoons 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 3 , 000 yards ( 2 , 700 m ) , while later it was extended to 6 , 000 yards ( 5 , 500 m ) , and yet again to 10 , 000 yards ( 9 , 100 m ) . 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 31 miles ( 50 km ) away . commanded by lieutenant colonel bruce mcdonald , the battalion was deployed with three of its four rifle companies forward at ( 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 7 , 700 yards ( 7 , 000 m ) . in support in west brigade was the british 4th light regiment , equipped with 105 - millimetre ( 4 . 1 in ) l5 pack and 5 . 5 - inch ( 140 mm ) medium guns . included were the guns of 102nd field battery , royal australian artillery , which had recently been deployed to west sarawak . by late april the australians began their first cross - border reconnaissance patrols . opposing them were a number of indonesian units , including elements of the para komando angkatan darat ( rpkad ) and the diponegoro division , normally based in 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 . these units were supported by at least two detachments of artillery , equipped with anti - aircraft machine - guns and 81 - millimetre ( 3 . 2 in ) mortars . battle first ambush , 27 may 1965 the first australian fighting patrol into kalimantan began on 24 may with two platoons , 5 and 11 platoons , 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 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 33 yards ( 30 m ) at that point . at 11 : 32 am , after occupying the position for only 40 minutes , motors were heard approaching along the river , with two 10 - foot ( 3 . 0 m ) 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 38 yards ( 35 m ) 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 11 yards ( 10 m ) . 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 81 - millimetre ( 3 . 2 in ) 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 , 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 , 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 , 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 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 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 .