EXTRACTION EXERCISE Marines extract a simulated casualty from an aircraft for a mass casualty exercise during a training exercise on Marine Corps Air Ground Combat Center Twentynine Palms, Calif., June 20, 2015. The Marines are assigned to the 4th Medical Battalion, 4th Marine Logistics Group, Marine Corps Forces Reserve. SHARE: Download: Full Size (0.04 MB) Credit: VIRIN: 485097-J-WYI35-523.jpg Photo Gallery