POMONA (CBSLA) – A man suspected of shooting two Pomona police officers Friday night, killing one of them, has been arrested Saturday afternoon after a more than 15-hour SWAT standoff at an evacuated apartment complex.

Los Angeles County Sheriff Jim McDonnell confirmed the arrest in a news conference. The standoff involving Pomona police and LASD deputies ended at approximately 2 p.m.

Late Saturday, the suspect was identified as 38-year-old Isaias De Jesus Valencia from Pomona

“For the last 15 hours, we attempted to make an arrest of this individual, and just did so successfully minutes ago,” McDonnell said.

The murdered officer was identified by the Los Angeles County coroner’s office as 30-year-old Greggory Casillas of Upland.

The other wounded officer, who was not named, was shot in the jaw and is in serious condition after undergoing surgery, a law enforcement source told KCAL9.

Casillas joined Pomona police in December 2014 as a record specialist before taking a position as a jailer in September 2015, Pomona Police Chief Michael Olivieri told reporters. He was sworn in as a Pomona police officer in September of 2017.

“He was just about to complete field training before the incident happened last night,” Olivieri said.

“Greg is a hero, a man to be looked up to,” Olivieri said. “He left his family at home to protect yours. And his ultimate sacrifice will never be forgotten.”

At a Saturday morning briefing, LASD Homicide Capt. Christopher Bergner said the incident began at 9:04 p.m. Friday when Pomona police were dispatched to a reckless vehicle.

The driver of the vehicle refused to stop, and a chase ensued, culminating in a traffic collision, Bergner said. The suspect then jumped out of the vehicle and ran, prompting a foot chase.

Witnesses told CBS2’s Greg Mills that the man was driving erratically.

“The guy was already driving crazy,” said Ruby Salas.

“It was like ‘oh my God,’ this is crazy. Like what is happening?” said Joanna Serrano. The suspect slammed into her dad’s Expedition when she and friends were standing next to it.

“We’re still trying to find out where he’s from, the reason that he ran,” Bergner said.

Valencia into the apartment complex in the 1400 block of South Palomares Street, entered a unit and barricaded himself in a bedroom. When the officers tried to make contact with him, he opened fire.

“As he barricaded himself in a bedroom, officers attempted to contact him, and he began firing through the door, striking two officers,” Bergner said.

“I heard something that sounded like machine guns, and it was probably shooting going on for about five minutes, it was pretty crazy,” neighbor and witness Marcos Vasquez told KCAL9.

Los Angeles County firefighters rushed the two officers to Pomona Valley Hospital Medical Center, where Casillas died.

An LASD SWAT team was called out and surrounded the complex, which was evacuated. LASD SWAT and crisis negotiators spent the night trying to negotiate with the man. Several flashbangs were set off and officers were also using a bullhorn. It is unclear how the suspect was taken into custody and what his condition was.

Neighbors told CBS2 that the suspect lives in the building.

Meanwhile, at around 6 a.m. Saturday, police escorted the body of the slain officer to the L.A. County Coroner’s Office in a procession of squad cars.

Governor Brown issued the following statement Saturday. It read in part,

“Anne and I are saddened by the tragic death of Officer Casillas early this morning. We offer our deepest condolences to his family and friends. His brave sacrifice will never be forgotten.

Officer Casillas is survived by his wife, Claudia Guzman, and two children.

In honor of Officer Casillas, Capitol flags will be flown at half-staff.”

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