The RDB took part in combat operations in Bosnia and Herzegovina and Croatia in support of ethnic Serb forces – often flying without any markings or only marked with the Serbian flag. In 1997, RDB combat units were reorganised into a Brigade level unit: the Unit for Special Forces (JSO), including the Aviation Unit. The JSO took part in numerous combat operations during the escalating Kosovo and Metochia crisis. Mi-24s were used to attack rebel training camps and hundreds of transport and medevac flight were carried out. During the NATO Operation Allied Force in 1999, JSO helicopters continued to fly liaison and medivac missions. During the NATO bombing, no helicopters were damaged but the fleet hangar was destroyed.