There are no injuries, Public Safety says.

By: KDKA-TV’s Jennifer Borrasso

PITTSBURGH (KDKA) — Pittsburgh Public Safety says law enforcement is investigating a bomb threat to the William S. Moorhead Federal Building.

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Officials say no device or threats were found Monday at the building on Liberty Avenue. Federal agencies are now trying to identify and locate the person who made the bomb threat. Public Safety says there were no injuries.

Sources told KDKA that a man called 911 just after 5 p.m. on Monday saying a bomb would go off in 18 minutes at the building.

(Photo Credit: KDKA)

Police evacuated the building and the federal courthouse around 5:25 p.m. and set up a perimeter. Law enforcement — including FBI, ATF, state and city police and K-9s — searched the building for anything suspicious.

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Police temporarily closed Seventh Avenue and Grant Street, 10th Street and Grant Avenue and Liberty Avenue and William Penn Place.

The building has offices for the ATF, IRS, and the U.S. Army Corps of Engineers. The building also houses other federal administrative offices.

David Richard was cleaning offices in the courthouse when the building was evacuated Monday night.

“I was just doing my job and over the intercom, they just came over and asked us all to please evacuate the building,” he said.

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The caller could face charges. Making a false threat is a crime.