 Hrkać was executed by shooting on 11 January 1978 in the Belgrade prison.Hrkać had maintained his innocence for both of the bombings, and over the years, it has been suggested that he may have been wrongfully executed.However, Amnesty International has recognized a theory that suggests Hrkać died of natural causes before the death sentence could be carried out, citing that, "Before his death, it is reported that his weight was half what it had been before he went to prison, that he had lost all his hair and had developed some symptoms of psychological disorder."