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Washington — A substance discovered in the White House complex that caused a brief shutdown of the facility Sunday evening tested positive for cocaine soon after it was found, according to two law enforcement officials and a recording of a radio dispatch from that night.

The substance was found in a common area of the West Wing, which houses the Oval Office and offices of some of the president’s top aides and support staff. A senior law enforcement official told CBS News the substance was found in a storage facility in a cubby routinely used by White House staff and guests to store cellphones.

The discovery of an “unknown item” prompted a “precautionary closure” of the White House, Secret Service spokesman Anthony Guglielmi acknowledged in a statement Tuesday. 

Guglielmi said that the D.C. Fire Department was called to evaluate the substance and determined it was “non-hazardous.” 

Further testing is taking place to confirm the substance is cocaine, and the agency is investigating how it got into the White House.

D.C. Fire hazmat personnel who responded to the scene Sunday night can be heard in a recording of a radio message saying that the substance tested positive for “cocaine hydrochloride.” The message was posted by the website OpenMHz, which records and archives radio dispatches by police, fire and EMS agencies.

President Biden was not at the White House over the weekend. He, first lady Dr. Jill Biden and members of their family departed for Camp David on Friday. They returned to the White House on Tuesday for an event with the National Education Association and Fourth of July festivities.