WASHINGTON — An explosion at a Montgomery County government lab may have been caused by a secret meth lab, according to a NBC Washington report.

On Saturday at 7:30 p.m., there was an explosion on the Gaithersburg, Maryland, campus of the National Institute of Standards and Technology — a federal entity that’s part of the U.S. Department of Commerce.

Investigators tell NBC Washington that they have recovered several chemicals, melted bottles and a recipe used to make meth at the facility.

“We are looking at the possibility that this was some sort of chemical reaction due to the manufacturing of drugs,” Montgomery County Police Capt. Paul Starks said to NBC Washington.

NBC Washington reports a NIST police officer who was hurt in the explosion is believed to have been cooking the chemicals, but the officer told authorities he was injured trying to fill his lighter with butane. The officer, formerly the second-in-command and acting chief of the NIST police, has resigned, NBC Washington reports.

No arrests had been made as of Monday evening.