CORONA (CBSLA) — The family of a man killed in a Corona Costco last month said they are still desperate for answers about what led to that fatal shooting that left two more injured.

It’s been six weeks since off-duty Los Angeles Police Department officer Salvador Sanchez fatally shot Kenneth French and seriously injured his parents. Family members are now taking to Facebook — this time calling out the Riverside County District Attorney’s Office, which they say has had the case for three weeks.

“The people of Corona/Riverside along with the mental health community are outraged and ready to protest,” the Facebook post said.

A family member told CBSLA’s Nicole Comstock that employees of the Costco have seen the security footage of the incident, and have told the family the video shows almost everything that happened June 14. Employees initially talked with CBSLA the night of the shooting, but the family alleges the company has made those who were there sign non-disclosure agreements effectively silencing them.

RELATED: Man Fatally Shot Inside Corona Costco Was ‘Non-Verbal, Never Violent’ Family Member Says

French’s family said they have been instructed not to speak on camera about the case, but one family member agreed to talk on the phone. He told CBSLA that the family does not dispute that French started the physical encounter by pushing or slapping Salvador. But the family member said witnesses told him that French’s mother Paola was shot first, in the back while standing between her mentally ill son and the officer. The family member said French’s father Russel was shot next while screaming, “Don’t shoot. My son is sick.”

Both are still under treatment for severe injuries.

The DA said the case was still under investigation, though the family is still asking for the release of the video.

“You can’t bury evidence under the guise of ‘under investigation’,” a Facebook post said.

Attorneys for Sanchez were not immediately available, but previously said the officer “feared for his life.”