3 LA sheriff's deputies killed in explosion at training facility in department's biggest loss of life since 1857

Three Los Angeles County sheriff’s deputies assigned to the arson explosives detail were killed in an explosion at a law enforcement training facility on Friday, the sheriff said.

These fatalities at the Biscailuz Training Center in Monterey Park mark the largest loss of life incident for the LA County Sheriff's Department since 1857, Sheriff Robert Luna said at a news conference.

No one else was hurt, the sheriff said, and the bomb squad rendered the scene safe.

The cause of the explosion is still not known, the sheriff said.

Luna called it an isolated incident and said there's no threat to the community.

Multiple law enforcement sources briefed on the investigation told ABC News that it appears an explosive had been brought back to the facility from a seemingly routine bomb squad callout on Thursday and was believed to have been inert when it later exploded.

In a statement Friday evening, the sheriff's department said authorities were returning to the Santa Monica residence where the deputies picked up the possible device that exploded and were planning to search the area for any potential explosive materials out of an abundance of caution.

"At this time, it is not determined if the devices found yesterday have any correlation to today’s critical incident," the sheriff's department statement said.

The three deputies were identified by the department Friday evening.

Detective Joshua Kelley-Eklund joined the department in 2006. A field training officer, he became a detective in 2016 and was assigned to a team investigating complex crimes. He became an arson and explosive investigator in 2022. He is survived by his wife and seven children.

Detective Victor Lemus joined the department in 2003, became a K-9 handler in 2017 and an arson investigator last year. He is survived by his wife, who is also a detective in the department, and three daughters. He also has three sisters who also work in the department.

Detective William Osborn joined the department in 1992. He worked as a detective for over a decade before becoming an emergency vehicle operations center instructor in 2016. He became an arson and explosive investigator in 2019 and took on the role of mentoring new investigators.

"These members, usually the average calls that they go to and dealing with some very dangerous situations or items, average about 1,100 per year. So these aren't people who don't do this very often. They are fantastic experts, and unfortunately, I lost three of them today," Luna said at the news conference.

Luna appeared emotional as he said he spoke with two of the three victims' families.

"As you can imagine, those were extremely challenging conversations," he said.

LA County Supervisor Janice Hahn in a statement called it "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. "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."

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 was also on the scene, Attorney General Pamela Bondi said.

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