RIVERSIDE (CBSLA) – Dozens of people held a demonstration outside the Riverside County District Attorney’s Office Wednesday to protest its decision not to bring charges against an off-duty Los Angeles police officer who opened fire inside a Corona Costco back in June, killing an intellectually-disabled man and critically wounding both his parents.

Oct. 9, 2019. (CBS2)

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On the night of June 14, 32-year-old Kenneth French of Riverside and his parents, Russell and Paola, were shot by off-duty LAPD Officer Salvador Sanchez.

The shooting occurred after a physical altercation between French and Sanchez. Surveillance video appeared to show French physically striking Sanchez while Sanchez was holding his 18-month-old son in his arms. Sanchez then fired off 10 rounds from a handgun.

Kenneth, who has been described as as schizophrenic and nonverbal, was killed. His parents were critically wounded but survived. Both were shot in the back.

An undated photo of 32-year-old Kenneth French, and his parents Russell and Paula French, who were shot by an off-duty LAPD officer at a Costco in Corona, Calif., on June 14, 2019. Kenneth died but his parents survived. (CBS2)

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A grand jury convened last month and recommended no criminal charges should be brought against Sanchez for the shooting.

Several family members of Kenneth took part in Wednesday’s protest, demanding that DA Mike Hestrin reconsider his decision not to prosecute Sanchez.

“He was murdered,” French’s cousin Jackie Shureih told CBS2 Wednesday. “You can’t claim self-defense if you’re shooting someone in the back from 20 feet away.”

The shooting created chaos in the store, sending shoppers scurrying for the exits. Corona police officers had initially responded to reports of an active shooter.

The French family has filed a complaint – the precursor to a lawsuit – against both LAPD and the city of L.A. that alleges Sanchez acted based on “inadequate and inappropriate training.”

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At last report, Sanchez, who has been with LAPD since 2012, has been on paid administrative leave.