During Vietnam war, when it left Da Nang in April 1971, the Third Marine Amphibious Brigade (3rd MAB) took its place at headquarters under Major General Alan J. Armstrong. The brigade began planning on March 1 with a target date for starting operations set at April 14. Assuming responsibility for over 13,600 marines who remained in Vietnam, 3rd MAB included a marine regiment, fixed-wing and helicopter gunships, and the remainder of a force logistics command. Remnants of the marine civic action program deactivated shortly, and 3rd MAB formally ceased to exist and was out of Vietnam by June 26, leaving behind a scattering of naval gunfire teams along the Demilitarized Zone, a marine advisory unit, a few officers at the Military Assistance Command, Vietnam (MACV), and guards for the U.S. embassy in Saigon— in a "transitional-support" group of some 500 marines.