The explosion was reported around 7:30 a.m. at the Biscailuz Training Facility, said Los Angeles County Sheriff’s Department spokesperson Nicole Nishida. She said three members of the department died.
It was not immediately known what caused the explosion or what the department members were doing at the time. Sheriff’s homicide detectives were on the scene.
An early line of the investigation was looking at a possible training accident, according to a law enforcement official briefed on the matter who was not authorized to discuss the matter by name and spoke to The Associated Press on condition of anonymity.
Attorney General Pam Bondi in a post on X said it "appears to be a horrific incident.” She said federal agents are at the scene to learn more.
“Please pray for the families of the sheriff’s deputies killed,” Bondi wrote.
