Mystery surrounds ambush killing of L.A. County sheriff's deputy: 'Somebody knows something'

The sun was about to set Saturday in the Antelope Valley when Los Angeles County Sheriff's Deputy Ryan Clinkunbroomer steered his patrol cruiser onto Sierra Highway and stopped at a red light outside the Palmdale sheriff's station.

Clinkunbroomer was dressed in his sheriff's uniform and on duty patrolling the high desert community of Palmdale, just north of Los Angeles.

Seconds later, a dark gray Toyota Corolla pulled up behind the marked black-and-white cruiser and paused, according to security video shared with The Times.

The sedan then pulled alongside the driver's side of the cruiser. It paused again, then sped off. Clinkunbroomer's vehicle drifted a foot or two.

In those seconds, authorities said, the deputy was shot in the head in a brazen ambush. He died from his injuries hours later. Clinkunbroomer was 30 years old.

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Sheriff Robert Luna on Sunday called the slaying a “targeted act” and asserted that Clinkunbroomer might have been killed because he worked in law enforcement.

“Somebody decided to shoot and murder him, I’m assuming at this point, because he was in uniform,” Luna said.

A passerby found the deputy unconscious in his vehicle at the intersection of Avenue Q and Sierra Highway around 6 p.m., officials said. Fellow deputies took him in critical condition to Antelope Valley Medical Center in Lancaster, and he died as physicians attempted to treat his gunshot wound.

Investigators worked through the night and all day Sunday, reviewing evidence, including surveillance footage, and interviewing potential witnesses. Luna said law enforcement at the local, state and federal levels had offered assistance. No suspects have been identified, and during a news conference Sunday evening, Luna pinpointed a "vehicle of interest" — the dark gray Toyota Corolla manufactured between 2006 and 2012. He asked anyone with images or knowledge of the vehicle to come forward.

"Whoever did this, I'd give in," Luna said Sunday evening. "We are going to find you."

Clinkunbroomer joined the department eight years ago and had been based out of the Palmdale station since 2018. For the last 18 months, he worked as a field training officer, a position that Luna said was for the "best of the best." Clinkunbroomer's family was steeped in law enforcement, and he was the third generation to work for the Sheriff's Department.

Luna said that four days before his death, the deputy had proposed to his fiancee.

"His father served with us. His grandfather served with us," Luna said. "He had so much ahead of him, and this coward, or cowards, took his life while he was sitting at a red light, waiting to serve his community."

"He had a good heart," said a colleague in the Sheriff's Department who spoke to The Times on the condition of anonymity because he was not authorized to talk to reporters. "Nobody has anything bad to say about him because he treated people and the public with respect."

Saturday's killing came three years after two Los Angeles County sheriff's deputies were shot several times while sitting in their parked patrol car in Compton. Both suffered severe wounds. A suspect was later arrested. In 2016, a veteran sheriff's deputy was shot and killed by a burglary suspect in neighboring Lancaster. The gunman was arrested shortly afterward.

Supervisor Kathryn Barger, whose district includes Palmdale, mourned Clinkunbroomer's killing and joined other officials calling for the gunman to be captured and held to account. Barger and Luna announced a $250,000 reward for information leading to the apprehension of anyone responsible in the deputy's slaying.

"It was an unprovoked attack on an honorable public servant," Barger said. "This heinous deed will not — will not — go unpunished. Whoever committed this cowardly act will be caught."

Dist. Atty. George Gascón and Luna stressed the need for help from the public. They encouraged anyone in the Palmdale area to pore over video footage in their possession from their cars, homes, business or cellphones, and said that any footage would help in the capture of the shooter. Those with information were asked to call homicide investigators at (323) 890-5500 or CrimeStoppers at (800) 222-TIPS.

“We’re gonna catch the person who did this,” Luna said. “Somebody saw something. Somebody knows something.”

Palmdale Mayor Laura Bettencourt called Clinkunbroomer a hero, declaring at a news conference, "The person that did that is a coward, and they will be caught."

Derek Hsieh, executive director of the Assn. for Los Angeles Deputy Sheriffs, a union representing rank-and-file deputies, said the slaying had sparked anger and sadness among their members and the wider police community.

"It’s an outrage," Hsieh told The Times. "An ambush is a targeted attack against law enforcement, and it sends a really clear message."

Gov. Gavin Newsom and acting Gov. Eleni Kounalakis said Clinkunbroomer's "commitment to service and justice represented the best of the Golden State," and they announced that flags at the state Capitol would be flown at half-staff.

Yellow tape surrounded the Palmdale sheriff’s station Sunday, and members of the public left roses, carnations and American flags at a makeshift memorial at the corner of Sierra Highway and Avenue Q.

Chris Altieri, 62, of Lancaster stood nearby holding a Blue Lives Matter flag as cars zipped down Sierra Highway. Some passersby waved; others honked their horns.

Altieri had arrived at 6:30 a.m. to wrap blue ribbons around the light posts. A Navy veteran who served for 24 years, he said he planned to stay most of the day.

“I know what it’s like to be a target, to be out in front and be down range,” said Altieri, wearing a cap that read “Freedom” beneath an American flag and blue gym shorts with “Navy” on the side.

“People put themselves out there, in front of your country and your community. That’s what these guys and gals do," Altieri said. "I wanted to put myself out here for them. For his family, for the police.”

Fred Sevilla, a longtime Palmdale resident, also turned out Sunday to pay his respects to the slain officer at the site where he was killed.

“I feel very heartbroken for the person who is not going home," Sevilla said.

At a nearby laundromat, resident Walter Flores, 30, sat on a bench with his two children, 1-year-old daughter Xyla and 3-month-old Exavier.

A Marine Corps veteran, Flores said he was shocked and saddened when he heard about the shooting.

“It’s terrifying that our own police force is in danger and that it happened so close to the police station," Flores said.

In a written tribute to Clinkunbroomer, employees at the Palmdale station said they were "numb with grief."

"Words cannot express the shock, sadness and anger over this senseless loss of an exemplary deputy and an even better human being," colleagues wrote in the statement. "He was very thorough in his investigations, genuinely cared for the community he served, and he was always willing to help out his partners any time they needed it.

"Ryan, we are so very sorry for your family and your fiancee. Rest assured, we will do our very best to take care of them in your absence."

Current and former Sheriff’s Department employees shared their anger and sadness as well.

“R.I.P. Deputy Clinkunbroomer; our partner and friend,” department employee Cynthia Knutson wrote on Facebook. She said others at the station were struggling to come to terms with the loss. “You will be greatly missed by us all here at Palmdale Station.”

Condolences and statements of solidarity poured in from other law enforcement agencies and organizations around Southern California and beyond.

Joe Gamaldi, vice president of the National Fraternal Order of Police, wrote on social media that he was “absolutely disgusted” by the killing, describing it as both an ambush and an execution “in cold blood by some dirtbag.”

Times staff writer Matt Hamilton contributed to this report.

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This story originally appeared in Los Angeles Times.