On 27 September 2004 , it was reported that British spies across the Balkans , including a SIS was chief officer in Belgrade and another spy in Sarajevo , were moved or forced to withdraw after they were publicly identified in a number of media reports planted by disgruntled local intelligence services – particularly in Croatia and Serbia . A third individual was branded a British spy in the Balkans and left the office of the High Representative in Bosnia , whilst a further two British intelligence officers working in Zagreb , remained in place despite their cover being blown in the local press . The exposure of the agents across the three capitals has markedly undermined the British intelligence operations in the area , including SIS efforts to capture The Hague 's most wanted men , which riled many local intelligence agencies in the Balkans , some of which are suspected of continuing ties to alleged war criminals . They were riled due to MI6 operating " not so much a spy network as a network of influence within Balkan security services and the media , " said the director of the International Crisis Group in Serbia and Bosnia , which caused some of them to be " upset " . In Serbia , the SIS station chief was forced to leave his post August 2004 after a campaign against him led by country 's DB intelligence agency , where his work investigating the 2003 assassination of the reformist prime minister Zoran Djindjic won him few friends
2003 assassination
Assassination of Zoran Đinđić
Secret Intelligence Service