An FBI Special Agent Bomb Technician instructs a group of 28th Civil Engineer Squadron Explosive Ordinance Disposal Airmen and members of various law enforcement agencies during a National Improvised Explosive Familiarization course at Ellsworth Air Force Base, S.D., July 12, 2017. The three-day, FBI-led, joint exercise taught EOD Airmen, along with other law enforcement agencies, how to create and recognize homemade explosives. (U.S. Air Force photo by Airman 1st Class Randahl J. Jenson)