The investigation continues Friday into the shootings which happened at about 10:30 p.m. Thursday at a base in Quantico about 40 miles south of Washington.
Military officials say the gunman was a marine who worked at an officer candidate's school.
He shot two of his colleagues there. Col. David Maxwell of Marine Corps Base Quantico said, "Two other victims-- a male and female-- both active duty marines, were pronounced dead at the scene."
Authorities say the gunman then killed himself in a barracks dorm room. All three were staff members at the officer candidate's school.
Officials in Virginia have not released the identities of the dead, pending notification of their families.
