Updated at 10:32 a.m. ET
The Washington, D.C., Police Department has issued an "all clear" at the Washington Navy Yard, the scene of a 2013 mass shooting, where there was a report today of possible gunshots.
The U.S. Navy also confirmed there was no sign of a shooting.
All personnel OK," the Navy said in a tweet. "Follow on NCIS investigation ongoing."
The report that came in about 7:30 a.m. resulted in a lockdown/shelter-in-place at the Navy Yard.
Police, the FBI, federal marshals and ambulances swarmed to the scene, and NBC News reported: "A first security sweep of the Navy Yard buildings found no evidence of a gunman." Police blocked nearby streets.
In 2013, a mass shooting at the Navy Yard killed 12 people, along with the gunman.
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