The Latest on the fatal police-involved shooting at a Costco Wholesale warehouse store in Corona.

A cousin of the man shot and killed by an off-duty police officer at a Costco Wholesale warehouse store in Corona says he was a "gentle giant" who was mentally disabled.

Corona police say Kenneth French attacked the Los Angeles Police Department officer, who was holding his young child, Friday night. The officer fatally shot French and critically wounded two others.

The Press-Enterprise reports that French's cousin Rick Shureih identified the other victims as French's parents, Russell and Paola French.

Shureih says French's family is seeking an attorney and declined to give specifics about his mental condition.

The officer's identity has not been released. The LAPD is conducting its own administrative investigation.

Corona police and the Riverside County district attorney's office are conducting a separate investigation and have not responded to requests for comment.