Backing the Blue
Police officers simulate treating a sucking chest wound during a training exercise Sept. 3, 2015 at Carl Ben Eielson Elementary School on Grand Forks Air Force Base, North Dakota. Nearly two dozen law enforcement officers from various agencies across the region came together here during the first week of September for some classroom and hands-on training dealing with a variety of active shooter scenarios led by trainers from U.S. Customs and Border Protection. (U.S. Air Force photo/Staff Sgt. Susan L. Davis)