A Bulgarian soldier strikes a bag with his baton while training in a non-lethal weapons class during exercise Platinum Wolf 2016 at Peacekeeping Operations Training Center South Base in Bujanovac, Serbia, May 13, 2016. Seven countries including Bosnia, Bulgaria, Macedonia, Montenegro, Slovenia, Serbia, and the United States joined together to conduct peacekeeping operations and non-lethal weapons training over the course of two weeks. (U.S. Marine Corps photo by Sgt. Sara Graham)