Master Sgt. Geoffrey Gay, a 201st RED HORSE, Det.1 member, plays the role of the active shooter during a major accident response exercise held at Horsham Air Guard Station, Pa., April 13, 2016. Gay has been asked to partake in this role for three prior MAREs that included an active-shooter element. (U.S. Air National Guard photo by Tech. Sgt. Andria Allmond)