A Prince George's County volunteer firefighter who was killed Monday night when the truck he had been riding in accidentally ran over him has been identified as Air Force 1st Lt. Michael P. McCarthy, a shift commander in a security police squadron at Andrews Air Force Base.

McCarthy, 25, a member of the Morningside Volunteer Fire Department for about a year, was responding to a report of a kitchen fire in the 7000 block of Bershire Drive, Camp Springs, fire officials said.

His truck, Engine 273 driven by a career firefighter assigned to the Morningside station, had to stop and back up while turning onto Bershire Drive from Allentown Road, according to a county fire spokesman. At that time, the spokesman said, McCarthy, riding on the right rear running board, "voluntarily stepped down without the driver's knowledge."

As the truck backed up, McCarthy was run over by its right rear wheels, the spokesman said. McCarthy, who was single, lived at the Morningside station, 5200 Suitland Rd. He had been assigned for the last 18 months to Andrews, where his job entailed supervising the "military working dog section," according to Capt. Clemmer Montague of the Andrews public affairs office. The dogs are used to accompany sentries and for narcotics identification.

McCarthy also was the officer in charge of the Andrews emergency services team, an elite unit activated in hostage or terrorist situations on the base. The son of an Air Force officer, he was born at Vandenberg Air Force Base, Calif.

Monday's accident was the second time in less than a year that a fire truck in the county accidentally ran over a firefighter. Last Sept. 28, Barbara (Sandy) Lee, a paid county firefighter, was critically injured when she fell from the side of a ladder truck and was run over by the truck's back wheels.