An off-duty Los Angeles police officer holding a child was knocked unconscious Friday in an unprovoked assault at a Costco in Corona and when he came to, he fired to protect himself and his son, the officer’s attorney said Monday. The shooting left a mentally disabled man dead and his parents injured and still in intensive care Monday.

Update: Family of man shot in Costco by off-duty LAPD officer calls for criminal prosecution

The lawyer for the officer on Monday offered, for the first time publicly, the officer’s account of what happened.

Attorney David Winslow said his client — whom he would not name — was struck from behind without a word being spoken while he was shopping with his wife and son. He was holding his 1 ½-year-old while feeding him teriyaki chicken samples, Winslow said.

Winslow said the officer was briefly knocked unconscious and his son also fell to the ground.

The attorney said the armed officer then returned to consciousness and believing that his life and his son’s life were in immediate danger, he began firing his gun.

“While lying injured on the Costco floor, he was unprotected and had no other option to defend himself and his son from further deadly attack. He was in fear for his son’s life. The only option was deadly force,” Winslow said.

He added that his client had no time to identify himself as a law enforcement officer as the event happened very quickly.

“He believed he was under attack,” Winslow said. “That’s when the shooting started.”

“The entire situation is a terrible tragedy for all concerned,” Winslow said.

Meanwhile, a spokesman for the Los Angeles Police Department said the agency also would not identify the officer, who is assigned to the department’s Southwest Division, until Corona police finish their investigation.

LAPD officials said the officer had been removed from the field and placed on a desk assignment for at least the remainder of the department’s administrative investigation into the shooting. That is a typical move after an officer-involved shooting.

The department will consider what Corona police learn about the incident when weighing any other action involving the officer.

“Corona is going to be answering some of our questions,” LAPD Officer Greg Kraft said.

Corona police did not release any new information on Monday about what happened Friday night: “The investigation is on-going and we want to make sure an accurate and detailed investigation is completed,” Sgt. Chad Fountain said in a statement.

Kenneth French, 32, died Friday night at Costco, with a cousin, Rick Shureih, saying the man was “non-violent, non-aggressive, non-verbal” and his typical behavior did not line up with Corona police’s description of the event as an unprovoked attack on the officer.

Winslow said the officer was not aware French had a disability.

Shureih said Monday the conditions of French’s parents, Russell French and Paola French, also struck with gunfire, were “still about the same” and that they remained in intensive care at a hospital.

The family was in the process of interviewing lawyers and wanted to see any surveillance video of the event that might exist and find out the name of the officer.

The off-duty officer suffered injuries and was treated and released. Winslow said he sustained a head injury caused by a “severe blow.” The child was uninjured. The officer was the only one who fired a gun, authorities have said.

Corona police have not said whether the LAPD officer used his department-issued weapon in the shooting.

Kraft, the LAPD spokesman, said on Monday it was not clear what weapon the officer had used: LAPD officers are allowed to carry their department-issued firearms while off-duty. But they can also carry any firearm that’s on a department list of pre-approved weapons.

Kraft said officers are not required to carry a gun while they’re off duty, but it is recommended. Officers are told if they become the victim of a crime while they’re out and about, and a perpetrator finds the officer’s badge or identification, the situation can become even more dangerous.

The team LAPD sent to the scene of the shooting on Friday was part of the department’s Force Investigation Division, which is responsible for investigating all shootings by LAPD officers.

“Even if it’s across the nation, we have to send a team,” Kraft said.

In recent years, increased public scrutiny of police shootings and uses-of-force has pressured the LAPD to release ever more information about incidents involving its officers. Through they’re often redacted, reports by the chief about each on- or off-duty shooting have long been made public. Now, the LAPD also releases a lot of video, if available.

Off-duty shootings are treated as administrative matters and do not get the same kind of information released as on-duty shootings, which can prompt the release of officers’ body-worn camera footage, audio from 911 calls, dashboard-camera footage, and video from security cameras that captured the incident, Kraft said.

That means the information the LAPD will release about the Costco shooting will be more limited, he said.

Three days after the shooting in Corona, shots rang out in the parking lot of another Costco — in Chula Vista in San Diego County. A gunman there on Monday afternoon shot and wounded two people, including his ex-girlfriend, and then killed himself.

The wounded victims were taken in serious condition to a hospital to undergo surgery. The woman’s child was in a stroller and wasn’t hurt.

The Associated Press contributed to this story.