An incident was reported at the Los Angeles County Sheriff's Department's Special Enforcement Bureau compound in East Los Angeles, July 18, 2025. KABC

(LOS ANGELES) --  Three Los Angeles County sheriff’s deputies were killed in an explosion at a law enforcement training facility on Friday, county officials said.

The victims appeared to be handling explosives when there was a blast, sources told ABC News. The Biscailuz Training Center in Monterey Park, a Special Enforcement Bureau compound, also houses the bomb squad, sources said.

The cause of the explosion is not known, according to LA County Supervisor Janice Hahn.

Arson investigators from the Bureau of Alcohol, Tobacco, Firearms and Explosives and the Los Angeles Fire Department are among those responding, LA Mayor Karen Bass said. The FBI is also on the scene, Attorney General Pamela Bondi said.

"This is an extraordinarily painful day for our Sheriff’s Department and for LA County. My prayers are with the families of the deputies and their colleagues in law enforcement who are reeling from this tragedy," Hahn said in a statement. "I am offering my full support to our Sheriff Robert Luna and his department as they not only work to support our deputies but to investigate what went so wrong. We need to get to the bottom of what happened and make sure that it never happens again."

"Please pray for the entire Los Angeles County Sheriff’s Department," Bondi wrote on social media.

This is a developing story. Please check back for updates.

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