On April 10 , 1957 , the 16th anniversary of the founding of the Independent State of Croatia , the 67 year old PaveliÄ was shot and seriously wounded by an unknown assailant in Buenos Aires . On 10 April 1957 , the 16th anniversary of the founding of the Independent State of Croatia , PaveliÄ was shot in the back and seriously wounded when getting off a bus in Lomas del Palomar near Buenos Aires . Although the assailant remains unknown , the attempt is usually attributed to Yugoslavian intelligence .