EAST LOS ANGELES (CNS) - The Los Angeles County Sheriff's Department is in mourning Saturday for three detectives killed in an explosion at a training facility in East Los Angeles in the agency's deadliest day since 1857.

Detectives Joshua Kelley-Eklund, Victor Lemus and William Osborn were identified by the department at 6:45 p.m. Friday as the personnel killed. They were all assigned to the Special Enforcement Bureau's Arson Explosives Detail.

"There are no words to express the pain and sorrow we feel," Sheriff Robert Luna said in a statement. "These heroes represented the best of our department, exemplifying courage, integrity and selfless service. This is not only a heartbreaking loss for their families, but for all of us."

Luna called the department's Special Enforcement Bureau, "The best of the best."

"The individuals who work our arson explosives detail, they have years of training," Luna said during a midday news conference Friday near the facility. "They are fantastic experts, and unfortunately, I lost three of them today."

The blast was reported at 7:25 a.m. Friday at the Biscailuz Regional Training Center in the 1000 block of North Eastern Avenue, southwest of the interchange of the San Bernardino (10) and Long Beach (710) freeways, according to the Sheriff's Information Bureau.

The detectives were moving ordnance in the training center's parking lot when the blast occurred, the Los Angeles Times reported.

Sheriff's deputies and some members of the public were visiting the site Saturday morning to pay respects to the detectives.

Luna said the site where the blast occurred was not rendered safe by investigators until late morning. He would not confirm reports suggesting the explosion involved unexploded ordnance that had been seized Thursday. However, on Friday, Santa Monica police, along with county and federal investigators, were seen searching an apartment complex in the 800 block of Bay Street, near Lincoln Boulevard.

A resident of that complex told KTLA5 that police and sheriff's officials had been at the building Thursday to retrieve some old grenades that a tenant found in a storage unit, apparently left behind by a previous tenant. The search on Friday afternoon prompted an evacuation of at least part of that apartment complex as investigators swept the property for any additional potentially dangerous materials.

The sheriff's department is investigating the apartment complex in connection with the explosion, department spokeswoman Nicole Nishida told The Times.

The three deputies killed in the blast responded to a call to assist the Santa Monica Police Department at the complex on Thursday, the newspaper reported. The explosion is being investigated as a negligent homicide, which could result in charges against the person who made or stored the device, law enforcement sources told The Times.

Los Angeles County Board of Supervisors Chair Kathryn Barger directed that county flags be flown at half-staff in honor of the fallen deputies.

"These were not just deputies, they were fathers, sons, mentors, and protectors who dedicated their lives to serving our communities with courage and honor," the LASD said.

"Deputy Joshua Kelley-Eklund, Deputy Victor Lemus, and Deputy William Osborn were members of our Arson and Explosives Detail. Each of them had years of experience, a deep commitment to their calling, and an unwavering sense of duty. To say we are heartbroken is an understatement. We are devastated, we are grieving, and we are holding close the families, friends, and colleagues who now carry the weight of unimaginable loss.

"But even through our sorrow, we will honor them. We will remember their dedication, their sacrifice, and their legacy."

A law enforcement procession began around 5 p.m. Friday to transfer the deputies' bodies from the training center for the county medical examiner's office. Dozens of sheriff's deputies stood in formation and saluted as the bodies were carried to a trio of medical examiner vans for the journey.

The vans were then escorted by deputies and other law enforcement representatives on the drive.

U.S. Attorney General Pam Bondi was among the federal officials to comment, saying on X that she had spoken with both Luna and U.S. Attorney in Los Angeles Bill Essayli. She also confirmed that the FBI and Bureau of Alcohol, Tobacco, Firearms and Explosives were assisting with the investigation.

"Our federal agents are at the scene and we are working to learn more," she wrote. "Please pray for the families of the sheriff's deputies killed."

The ATF announced it has activated its National Response Team to deploy to the scene of the explosion. The team consists of special agents, certified fire investigators, a forensic chemist, intelligence research specialist, certified explosives specialist, law enforcement training specialist, fire protection engineer, electrical engineer and an accelerant detection dog with handler, according to the bureau.

Los Angeles Mayor Karen Bass said the city was supporting the investigation with Los Angeles Fire Department arson investigators and LAPD bomb squad personnel.

"The thoughts of all Angelenos are with all of these impacted by this blast," Bass said on X.

Gov. Gavin Newsom said he was briefed on the blast, and that the Governor's Office of Emergency Services was in contact with the sheriff's department and closely monitoring the situation, offering "full state assistance."

Newsom's office also announced the state had deployed investigative personnel from the Office of the State Fire Marshal at the request of the ATF.

Luna called Friday's blast "the largest loss of life for us as the L.A. County Sheriff's Department since 1857." That was when Sheriff James Barton and several members of his posse, including three deputies, were ambushed in present-day Santa Ana by criminals they were pursuing. Barton died just three weeks into his second term, according to a sheriff's department online historical timeline.

Kelley-Eklund joined the LASD in March 2006 and was later assigned to the Pitchess Detention Center North and North County Correctional Facility. He transferred to the Lennox station in 2010 and became a field training officer at the South Los Angeles station, mentoring trainees.

Kelley-Eklund was promoted to the rank of detective at the Narcotics Bureau in 2016, and was assigned to the LA Impact Team investigating complex crimes, seizing large quantities of narcotics, and assisting in the arrests of murder suspects. In 2022, he became an Arson and Explosive Investigator with the Special Enforcement Bureau and received his bomb tech certifications as well as other training accolades.

Kelley-Eklund is survived by his wife, Jessica Eklund, and their seven children.

Victor Lemus joined the LASD on July 1, 2003, as a security assistant. He completed the Deputy Sheriff Academy in 2003 before he was assigned to the Twin Towers Correctional Facility where he ran on the Baker to Vegas running team. Following that, he transferred to the LASD's Century station, where he worked as a senior training officer and detective. He transferred to the Special Enforcement Bureau in 2017 where he was assigned as a K-9 handler prior to becoming an arson and explosive investigator last year. He received commendations for his ability to mentor and train fellow deputies as well as notable arrests involving career criminals.

Lemus is survived by his wife, LASD Detective Nancy Lemus, and three daughters. He has three sisters who are also in the department. He is also survived by his brothers Alfredo, Pedro, Juan, and Efren and brother-in-law Sgt. Robert Catalan, who is assigned to the LASD's Carson station.

Osborn graduated from the Sheriff's Academy in February 1992 and was assigned to the Men's Central Jail. He transferred to Pico Rivera station in 1998 as a patrol deputy, and to the Industry station in 2001 before he was promoted to detective, where he received commendations for his work recovering stolen vehicles.

Osborn transferred to the Training Bureau as an Emergency Vehicle Operations Center instructor in 2016, but his love for investigations drew him back to detective work and he joined the Special Enforcement Bureau as an arson and explosive investigator in 2019, handling cases involving high-dollar loss fires in residential properties, as well as fires involving the loss of life. He was described as "one of (the) tenured bomb technicians regularly relied upon when faced with a new challenge. He has broad range of experience and could be relied upon to provide relevant insight on broad range of subjects."

He is survived by his wife, Detective Shannon Rincon, four sons, and two daughters.

Details regarding memorial services will be announced in the coming days, according to the LASD.

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