Costas Georgiou Costas Georgiou ( , also Anglicized as Kostas Giorgiou ; alias " Colonel Callan " ) ( 1951 – 10 July 1976 ) was an ethnic Greek Cypriot , British mercenary executed following the Luanda Trial for activities during the civil war phase of the Angolan War of Independence . Early life . Georgiou was born on Cyprus in 1951 , when the island was still a British protectorate . His family moved to London in the early 1960s . British military career . Georgiou joined the British Army and served , at first with distinction , in 1st Battalion , Parachute Regiment in Northern Ireland . He was credited as being one of the best marksmen in the unit , and he was also alleged to have fired 26 shots on Bloody Sunday when civilians were killed in Derry . Despite later claiming to have been a colonel , Georgiou ' s highest British Army rank attained was that of corporal , and he never received officer training . Others state Georgiou was a private soldier . Mercenary activity . Background : Roots of the conflict and Georgiou ' s recruitment . In 1975 , Portugal recognized the independence of its former colony of Angola , and acknowledged the Soviet - aligned MPLA faction as the de jure government . The new government sought and received help in the form of Cuban military advisors , combat troops and material to fight against rival factions , which included the U . S . - backed FNLA and the South African - backed UNITA , which received some US funding but no actual military aid . At the same time , British and American ex - military were recruited by FNLA through Private Military Companies ( PMC ; also known as PMIs , for " Private Military Industry " ) in the United Kingdom and United States . Funding was provided by various NATO - member intelligence organizations , including the American CIA and the French Secret Service . By this time , Georgiou was out of the army and working part - time in construction . He had few prospects for more stable and gainful employment , given his dishonorable discharge for his part in robbing a post office . He was dating a Greek Cypriot woman , Rona Angelo . Her cousin was ' Shotgun ' Charlie Christodoulou , like Costas an ex - paratrooper of Greek Cypriot extraction , but honorably discharged . An acquaintance , Nick Hall , another dishonorably discharged airborne veteran , took the initiative of putting out an advertisement soliciting mercenary employment for four able - bodied young men . These would be Hall himself , Georgiou , Christodoulou and Costas ' s old comrade , Mick Wainhouse . The men received a prompt reply from " Dr . " Donald Belford , a former British Army medic who had volunteered for a humanitarian aid group in Africa some years before . While there , he had treated several Angolan fighters wounded in the struggle against the Portuguese , earning their friendship and trust . One of his friends was Holden Roberto , leader of the FNLA . After independence , Belford became Roberto ' s official emissary in the United Kingdom . Georgiou in Angola . " Colonel Tony Callan , " as Georgiou was now styling himself - the surname having come from the popular hardbitten espionage and action series Callan , starring Edward Woodward as a hired gun for the Crown - went to Angola to work as an unpaid medical orderly , in advance of his three colleagues . It was while he was working in this position that he took part in the decisive action that brought him to the notice of the FNLA leadership . When FNLA soldiers fled the advance of a UNITA force , which threatened to capture the hospital to which he was assigned , Georgious led a handful of Portuguese FNLA soldiers in an offensive defence , stopping the MPLA force in its tracks . The general trend of the war , for the FNLA , at that time was one of a steady string of defeats , ensuring that the defeat of the MPLA column attracted immediate attention from Holden Roberto , who , to Georgiou ' s surprise , appointed him head of the FNLA army , with the rank of Colonel ; still unpaid . His three friends arrived from Britain shortly after . Together with the Angolan soldiers , Callan led a small FNLA military group composed of mostly Portuguese and Greek Cypriot mercenaries with the odd Irishman , Lyndon Sheehan , thrown in . One of the Portuguese , who styled himself " Madeira " after the famous fortified wine , was also a former champion boxer . This group were all excellent , experienced soldiers , but far too few in numbers to accomplish a decisive victory . Still , the record they amassed in their short guerilla campaign was impressive . In one ambush on an MPLA column , the squad - sized unit , led by Sheehan , killed 60 of the approximately 600 MPLA and Cuban fighters , and destroyed four T - 34 ' s and four " Stalin organ " mobile rocket platforms , Sheehan lost four men in this firefight . Impressed with their efforts , Holden Roberto dispatched Nick Hall back to England to recruit a full battalion . Thanks to ongoing recruitment in England , a somewhat larger mercenary contingent was formed , but a full battalion was never realized . The enlarged force was still rather small relative to MPLA / Cuban forces , and many of the men were civilians with no military experience . Many refused to submit to military discipline . This , combined with the foreign , Mediterranean origin of most of the core leadership ( Georgiou , Christodoulou and the Portuguese ) , created a deep gulf between the officers and British men — to say nothing of the native Angolans recruited as infantry and support troops . Most of these had no military experience , and many knew no English or even Portuguese , then still the language of government and the native elite . The first contingent of mercenaries was mostly made up of professional soldiers , selected by a British PMC , Security Advisory Services ( SAS ) , run by John Banks , Chris Depmster , and Dave Tomkins . Georgiou resented SAS ' s own leadership structure within the group , and perceived John Banks , who remained in Britain , personally as a threat to his own position when Banks visited Angola . Georgiou became increasingly paranoid and belligrent to his own men , murdering African soldiers and creating a climate of fear even among the British mercenaries , none of which aided the morale of the FNLA forces , or their ability to wage war successfully against the MPLA . The second contingent of mercenaries sent from Britain , unlike the first , was made up mostly of working class men with no military experience . These undisciplined men quickly surmised the perilous situation into which they had been placed , and the instability of their leadership . A group of them consequently seized vehicles and attempted to flee the country , firing on other FNLA forces in the process , including Chris Dempster . The deserters were quickly rounded up by Georgiou ' s men , and fourteen were summarily executed by firing squad . A third contingent of similarly inept mercenaries was recruited in the US by an American PMC . The " battalion " fought several more dramatic engagements , including successful ambushes of minor MPLA detachments . However , given his limited resources and the fact that many of his men — European and native alike — were untrained , increasingly demoralised amateurs , Georgiou ' s campaign was ultimately a failure . According to mercenary David Tomkins , the group spent most of its time foraging for food , usable weapons , and ammunition . Much of this foraging consisted of " raids " on villages where the men would casually walk into town brandishing their weapons , searching for anything of use . Anyone who offered violent resistance would be shot , although Tomkins said in an interview that this was rare . Lack of proper equipment was one of the key factors in the failure of foreign mercenary units in Angola generally , and in Georgiou ' s case in particular . The MPLA had Soviet tanks , artillery and crack Cuban troops . The other two factions had mostly light infantry , not always the best trained and disciplined either . Another factor was leadership inexperience : Georgiou had absolutely no training nor experience as a commissioned officer , nor did most of his counterparts in other units . Trial and execution . The principal crime for which Georgiou was convicted during the Luanda Trial , and subsequently executed , was the slaying of fourteen of his men who had attempted to desert in some of the trucks that were carrying the unit ' s supplies . They did this after mistakenly firing on one of the other vehicles in their convoy , for which they feared punishment . He was also accused of killing two Angolan civilians , as well as torturing civilians to extract intelligence on enemy troop movements . In addition , fighting as a rebel soldier was itself considered a crime by the prosecuting MPLA authorities . Colonel Callan as he used to call himself , killed all of his fourteen or ten men just because they ran away from the position which was under their surveillance . The place used to be called Sanza Pombo . At that time Callan was stationed at S . Salvador . Georgiou ' s sister was allowed to visit him during his captivity in Angola . In a BBC interview , she said they spoke mainly about their family and the trial proceedings . They conversed in Greek . Georgiou ' s body was repatriated to England , and he was buried according to the rites of the Greek Orthodox Church .