UPDATE (1pm, 9/16/13): At least 12 are confirmed dead in the Navy shipyard shooting, and the one known gunman killed. Police say there is the possibility there was more than one active shooter.
UPDATE (11am, 9/16/13): Multiple news sources are reporting the gunman is dead. Source tell ABC News shooter was a former Navy official in his 50's whose work status recently changed.
ABC News -- An armed suspect is still at large after he fired shots inside the Navy Sea Systems Command headquarters building in Washington, D.C., this morning, killing at least four people including two officers, and wounding at least 6 others.
The suspect is being described as a thin, bald, black male carrying what appeared to be a semi-automatic rifle.
The incident occurred in a 3,000-person building at 8:20 a.m. Law enforcement officials initially told personnel to evacuate the building but they are now being held in a shelter in place position.
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