Man arrested in killing of Pomona police officer, ending long standoff

L.A. County sheriff's deputies escort a handcuffed man suspected of fatally shooting a Pomona police officer to a waiting car on Saturday.
(Irfan Khan / Los Angeles Times)

A man suspected of killing one Pomona police officer and wounding another was arrested Saturday afternoon after an overnight standoff at the apartment complex where the shooting occurred.

The dead officer has been identified as Greggory Casillas, 30, said Pomona Police Lt. Eddie Vazquez.

For the record:

10:25 p.m. March 10, 2018Previous versions of this story misspelled Greggory Casillas’ first name as Gregory and said he was 25 years old. He was 30.

Officials said the suspect, identified as Isaias De Jesus Valencia, 39, was being pursued by police Friday night when his car crashed near the apartment complex. The man ran from his vehicle and was followed by officers on foot.

He went into the apartment complex and barricaded himself inside one of the units. When officers arrived, authorities said, he fired through a door, striking the two officers.


The second officer was shot in the face as he attempted to rescue Casillas, Los Angeles County Sheriff Jim McDonnell said at a news conference Saturday afternoon.

It’s “tough right now,” McDonnell said. “Our thoughts and prayers go out to the Pomona Police Department. It is a family. Everyone is impacted by this.”

During the standoff, deputies used tear gas to get the suspect to surrender, but he refused to comply, according to the Sheriff’s Department. Deputies with the Special Enforcement Bureau eventually entered the building and deployed a police dog.

Valencia was arrested on suspicion of murder and attempting to murder police officers and is being held without bail.

McDonnell said authorities can start the “actual investigation” now that the suspect has been arrested.

Media briefing on standoff with suspect in fatal shooting of Pomona police officer (Video by Irfan Khan / Los Angeles Times)

“It has been a long night,” he said.

Casillas was sworn in as a Pomona police officer in September 2017, Pomona Police Chief Michael Olivieri told reporters. He was nearly finished with his field training when he was killed.

“It’s a sad day for our community and a sad day for law enforcement in general,” Olivieri said. “He left his family at home to protect yours.”

Raised in Los Angeles County, Casillas attended “local colleges and universities,” Olivieri said. He is survived by his wife and two children, as well as his parents and two brothers.

Olivieri called Casillas a hero, and a “man to be looked up to.” He had worked in different positions within law enforcement — as a records specialist and jailer before becoming a police recruit — to “better prepare himself to achieve his goal” of becoming an officer.

“His ultimate sacrifice will never be forgotten,” Olivieri said.

At the end of the news conference, sheriff’s deputies surrounded Olivieri as he walked away from the crowd. Some patted him on the back.

Earlier Saturday, more than a dozen Pomona police officers, L.A. County sheriff’s deputies and county fire vehicles blocked the street in front of the apartment building where the suspect was barricaded. A handful of SWAT officers were gathered outside the entrance to the beige structure. Every so often, their muffled megaphone calls to the man to come out echoed through the street.

Police Officer Greggory Casillas was shot and killed as he attempted to arrest a man.
(Pomona Police Department )

Neighbors, some wrapped in blankets or wearing hooded jackets, watched the scene unfold from behind police tape. A few stood on top of their cars in the rain for a better view when a flash-bang device detonated about 10 a.m. An officer then again ordered the man to exit through the front door.

“Come outside with your hands up,” the officer said. “Come on out.”

About 9:10 p.m. Friday, dispatchers relayed reports of an officer down in the 1400 block of South Palomares Street near Fernleaf Avenue. A law enforcement source said about 75 officers from several agencies converged on the scene but were unable to move the wounded officers to safety at first because of gunfire.

The L.A. County Fire Department was called about 9:30 p.m. to assist, said dispatch supervisor Jeremy Stafford.

Local news footage showed officers trying to perform CPR on a man lying on the pavement.

A mother and daughter who live nearby said they ran out of their apartment after hearing the crash Friday night. A beige truck crashed into a parked red truck in front of an apartment complex, said the pair, who gave only their first names.

Marlene, 12, said she saw the suspect exit the beige truck with a gun tucked under his arm. He then ran into the nearby apartment. Marlene recorded a portion of the shooting.

(Los Angeles Times )

The video shows Marlene and her mother, Jessica, 29, running for safety as the gunfire continues.

“He’s inside,” a woman says in the video. “Let’s go!”

Marlene said she saw police bring a wounded officer outside and rip off his vest. In the cellphone footage, a group of officers surrounds another officer on the ground as one performs chest compressions.

Marlene and other neighbors said they spotted a woman they said was the suspect’s mother crying and vomiting outside the apartment building before she got into a police SUV.

“I was scared,” Marlene said.

Ninfa Martínez said she saw residents running out of the building where the shooting occurred.

“Then I heard some shots and went back running” Martínez, 24, said. “It was crazy.”

Once the gunfire stopped, her mother and other neighbors offered coffee to those outside, she said. Some of the displaced residents slept in their cars, she said. Martínez and her mother slept for an hour, until just before 6 a.m.

The shooting sparked an outpouring of support from local law enforcement.

“Our thoughts and prayers are with Pomona police,” the Sheriff’s Department said in a statement.

“Another hero gone too soon. These tragedies are occurring too often, and the pains of sacrifice will never be forgotten,” added LAPD Chief Charlie Beck.

Casillas’ body was escorted by a police procession Saturday morning as it was transferred from Pomona Valley Hospital Medical Center to the coroner’s office.

The last law enforcement officer killed in the line of duty in Southern California died a little over a year ago.

Whittier Police Officer Keith Boyer was fatally shot while investigating a traffic crash in February 2017.

Michael C. Mejia, 27, a convicted felon with a history of drug possession and violent criminal activity, is accused of killing his cousin and stealing his car in East Los Angeles before crashing into two other vehicles at a Whittier intersection.

When Boyer, 53, and his partner, Patrick Hazell, arrived at the scene and ordered Mejia out of his car, he opened fire on them, prosecutors said. Boyer died and Hazell was wounded.

Times staff writer Alene Tchekmedyian contributed to this report.


8:50 p.m.: This article was updated with the suspect’s identity.

3 p.m.: This article was updated with comments from a press conference.

2 p.m.: This article was updated with comments from residents.

11:40 a.m.: This article was updated with the identity of the dead police officer.

10 a.m.: This article was updated with police using a flash-bang device to try to capture the suspect and other details.

8:30 a.m.: This article was updated with additional details about the shooting.

7:30 a.m.: This article was updated with activity at an apartment.

5:55 a.m.: This article was updated with background on Whittier shooting.

5 a.m.: This article was updated with new details.

1:55 a.m.: This article was updated with one officer’s death.

March 10, 12:20 a.m.: This article was updated with L.A. County homicide detectives responding.

11:40 p.m.: This article was updated with two officers wounded.

11:20 p.m.: This article was updated with additional details.

This article was originally published at 10:55 p.m. March 9.