At the end of World War II, the Communist authorities pursued a strict set of policies which could be deemed as a form of denazification, only more similar to the Soviet style than to the American style. People who collaborated with the Ustaše were often court-martialled at the end of the war, and there were extrajudicial killings of collaborationist troops that refused to surrender. Trials against suspected collaborators continued long after the end of the war. In the 1980s, Andrija Artuković was extradited to Yugoslavia from the United States, and prosecuted in SR Croatia where he died in a prison hospital. The secret service exercised harsh control over both citizens with links to the Ustaše and mere Croatian nationalists. UDBA continuously monitored the Croatian diaspora, and was implicated in numerous assassinations, notably that of Bruno Bušić in 1978.