Authorities Give All Clear After Security Lockdown at Navy Yard

(Bloomberg) -- U.S. Park Police and local units respond to reports of an active shooter at the Washington Navy Yard, according to WUSA. The Washington Navy Yard is the site of an attack by a gunman who killed 12 people in September 2013. (Source: ABC)

Law enforcement officials declared the Washington Navy Yard safe after a security lockdown prompted by a report of gun shots that later proved unfounded.

Dozens of police units swarmed the military installation less than two miles from the U.S. Capitol after an initial report of gunfire. Within three hours, they began to leave as the FBI gave the all-clear signal. There were no reports any injuries and the Navy said all personnel were accounted for.

The Washington Metropolitan Police Department said on Twitter that a caller inside the complex reported “possible sounds of gun shots” at 7:29 a.m. Washington time.

“At this time we have completed our search of the building and have found no evidence of a shooting or injured personnel,” the police tweeted.

Security was stepped up at U.S. government buildings in the nation’s capital in response to the alert, on the eve of the July 4 holiday weekend.

Secret Service agents cleared tourists from the area in front of the White House and shut down Lafayette Park across the street.

U.S. Capitol Police sent additional agents to the Capitol grounds, the agency said.

“There is no known threat to the Capitol Complex,” Lieutenant Kimberly Schneider, a spokeswoman for the Capitol Police said Thursday morning in an e-mailed statement.

The Navy Yard was the site of a mass shooting in 2013, when contractor Aaron Alexis killed a dozen people. Alexis was killed in a shootout with officers.

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