The 191st Special Activities Division, also known as the Covert Action Group, is a military special operations force under the joint command of the UNSC Army Intelligence Activity (AIA) and Office of Naval Intelligence (ONI), responsible for conducting covert and black operations during times of war and turmoil. It is composed of four independent regiments (86th CAR, 22nd CAR, 17th CAR, 93rd CAR) and the attached 160th Special Operations Aviation Regiment, and is headed jointly by uniformed officer staff of the UNSC Army, Navy, and Marine Corps, as well as by political officer staff of the Unified Earth Government and subordinate Colonial Administration Authority.