Based on recently discovered documents from the Slovene Archives the author analyzes the circumstances of and the reasons for the mysterious death of British Major Alfgar Hesketh-Prichard (alias Major Cahusac). Prichard was killed on Svinška Planina in Carinthia, now a part of Austria, in the winter of 1944/45. He was a member of Special Operations (SOE) Clowder Mission, whose task was to organize the rebellion of Austrians against the Nazis. This, however, did not please political leaders of the Slovene resistance who perceived an independent Austrian resistance movement as a threat to Slovene interests concerning the future changes of Yugoslav borders that were to take place after the end of the war. It was decided that Major Cahusac should be executed in secret, and Jože Ulčar – Mirko was chosen for this highly confidential task. Ulčar was commander of the batallion with which Prichard set over the Drava in the night between October 14 and 15, 1944. Due to Prichard’s intervention, the batallion had been well armed by the SOE. The execution took place on December 3, 1944 close to St. Oswald; Prichard’s body was found in 1950 by two hunters. Until the recent discovery of certain documents related to it, the circumstances of Prichard’s death, the perpetrator and those who had ordered his execution remained unknown.