The 9th Corps of the Yugoslav People 's Army ( `` Jugoslovenska Narodna Armija '' – JNA ) led by Colonel Ratko Mladić and the forces of the Serbian Autonomous Oblast ( region ) of Krajina ( SAO Krajina ) under Knin police chief Milan Martić besieged Besieging the Croat-inhabited village of Kijevo in late April and early May 1991 .

Their superiors , Radovan Karadžić and Ratko Mladić , were also convicted .