The parents of a man with developmental disabilities who was shot and killed in a Costco by an off-duty police officer said they pleaded with the fellow shopper not to fire his weapon as their son was not a threat.

Russell and Paola French, who were both severely injured in the June 14 shooting in Corona, east of Los Angeles, spoke publicly for the first time since their son Kenneth, 32, was fatally shot by Los Angeles police officer Salvador Sanchez.

Sanchez maintains he opened fire after he was knocked down with his infant son in his arms.

Russell French, who was shot in his chest and abdomen and lost a kidney, said at a news conference Monday that he "begged" Sanchez not to fire. "I told him we had no guns and my son was sick."

Paola French, who was shot in the back and ended up in a coma, said she "was pleading for my son and our lives."

"What threat did I pose to him?" she asked. Her son was a "peaceful and loving soul" who was never aggressive, she said.

No one in the French family was armed at the time of the shooting.

Corona police said Kenneth French assaulted Sanchez without provocation. An attorney for Sanchez, David Winslow, said the officer was shopping in Costco with his wife and had his infant son in his arms when they were "both knocked to the ground."

"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," the lawyer said in a statement following the incident. He said the "only option" was for the officer to use deadly force.

Ira Salzman, another attorney representing Sanchez, told The Associated Press that the officer was "assaulted" and "acting in self-defense."

"It's a horrible tragedy for both families," Salzman said.

An attorney for the French family, Dale Galipo, said Monday that Kenneth French, who was nonverbal, might have pushed the officer from behind, but the action wasn't an attack, and the French family quickly moved away.

"It certainly does not justify killing someone," Galipo said, adding that Sanchez should face murder or manslaughter charges. The attorney said he's not sure if there was an altercation before the shooting, and urged authorities to release footage from the scene.

But a judge has ordered that videos remain sealed to the public for a year pending an investigation by prosecutors who are deciding whether to file criminal charges.

The French family on Monday filed a claim for unspecified damages against the Los Angeles Police Department, the City of Los Angeles and Sanchez.

The claim said Sanchez identified himself as a LAPD officer before the shooting and fired his LAPD-issued weapon, but he "failed to give the French family a verbal warning that deadly force would be used prior to the shooting," and ignored the couple's pleas not to shoot.

"The shooting of Kenneth, Russell and Paola French was unjustified, unreasonable and completely excessive, particularly because neither Kenneth, Russell, nor Paola French posed an immediate threat of death or serious bodily injury to any person, including officer Sanchez, at the time of the shooting," the claim said.

It said Russell and Paola French have suffered from emotional distress after the shooting, and have mounting medical bills from multiple surgeries and required home health care.

A spokesman for the LAPD said the department does not comment on pending litigation. Sanchez is on paid administrative leave, which is mandatory following an officer-involved shooting.