With the 6 April 1941 Nazi German invasion of the Yugoslav kingdom, the country was quickly dismembered into several client states, the biggest of which was the Ustaše-run Independent State of Croatia that swallowed up all of Bosnia including the city of Sarajevo. German units marched into Sarajevo on 15 April setting the scene for the first Ustaše contingent to enter the city en route from Zagreb during the night of 23–24 April. Within weeks of their arrival, on 5 May 1941 Ustaše arrested dr. Dušan Jeftanović along with several other prominent Sarajevo Serbs. He was taken to Zagreb where for some time he had been detained in the Petrinjska Street police jail before Ustaše eventually executed him.