Trifko Grabež society. For the next two years he spent most of his spare time with other nationalists who favoured a union between Bosnia and Herzegovina and Serbia. When it was announced that Archduke Franz Ferdinand, the heir to the throne of Austro-Hungarian Empire, was going to visit Bosnia and Herzegovina in June 1914, Colonel Dragutin Dimitrijević, the chief of the Intelligence Department in the Serbian Army and head of the Black Hand, sent seven men, Grabež, Nedeljko Čabrinović, Vaso Čubrilović, Cvjetko Popović, Danilo Ilić, Muhamed Mehmedbašić and Gavrilo Princip to Sarajevo to assassinate him. Each man was given either a revolver
Leopold Lojka as Ferdinand's car began to pull into it. Princip seized his chance and with his Model 1910 7.65 mm FN Browning in hand he lunged through the crowd. Lojka was attempting to reverse, and Gavrilo Princip shot and killed the Archduke, shooting him in the jugular vein, and his expectant wife, in the stomach. After the assassination, Lojka was given the task of sending three telegrams of apology: one to the Austro-Hungarian Emperor Franz Joseph, one to the German Emperor Wilhelm II, and one to the children of Archduke Franz Ferdinand. He also served as a witness for the prosecution