D.C. police and the FBI say there's a report of a shooter inside a military building at the Washington Navy Yard.
Police are responding to reports of shots fired, and an FBI spokeswoman says there's at least one victim.
The U.S. Navy also said on Twitter that they're looking for a gunman. They say three shots were fired inside their Naval Sea Systems Command headquarters.
The Washington Navy Yard says on its website that it's the Navy's oldest shore establishment. It is home to the chief of Naval Operations and is also headquarters for the Naval Historical Center and numerous naval commands.