On Sunday, 28 June 1914, Franz Ferdinand and Sophie von Chotkow were assassinated by Princip. Princip and Nedeljko Čabrinović were captured and interrogated by the police. They held out, but Ilić, who was picked up on a routine check, eventually broke down under pressure and named his fellow conspirators. Muhamed Mehmedbašić managed to escape to Serbia but Veljko Čubrilović, Vaso Čubrilović, Cvjetko Popović and Miško Jovanović as well as Danilo Ilić were arrested and charged with treason and murder.
Eight of the men charged with treason and the murder of Archduke Franz Ferdinand were found guilty. Under Austria-Hungarian law, capital punishment could not be imposed on someone who was under the age of twenty when they had committed the crime. Nedeljko Čabrinović, Gavrilo Princip and Trifko Grabež therefore received the maximum penalty of twenty years, whereas Vaso Čubrilović got 16 years and Cvjetko Popović 13 years. Ilić, Veljko Čubrilovic and Miško Jovanović, who helped the assassins kill the royal couple, were executed at the Sarajevo barracks on 3 February 1915.[3]