Senior Airman James Colombo, 422nd Security Forces Squadron unit trainer, jogs along the perimeter road at RAF Croughton, England, May 11, 2015, while carrying a guidon and wearing a gas mask, during a ruck march in honor of National Police Week. Colombo said he carried the extra gear to show his support for law enforcement officers who gave their lives in the line of duty. (U.S. Air Force photo by Staff Sgt. Jarad A. Denton/Released)