WASHINGTON - An unidentified white substance found at the U.S. Attorney's office in the District of Columbia has been cleared. Tests have shown the substance is not dangerous.
Battalion Chief Brian Lee, a D.C. fire department spokesman, says workers at the building have been permitted to return to their offices.
He earlier said that four people who were exposed to the substance were being evaluated.
The substance was reported as a white powder coming from either an envelope or package. It wasn't immediately clear what the substance is, though Lee says tests showed it's not dangerous.
The building is in the Judiciary Square area of the city, near multiple courthouses.
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