click to enlarge SF Examiner/File photo

Luis Gongora's knife.

Luis Gongora, the 45-year old homeless man shot and killed by San Francisco police on April 7, was prone on the ground when he was fatally shot in the head, according to results of a private autopsy released Friday. Gongora died from a gunshot wound to the head "fired from above," according to a claim against the city filed by his family. A claim is the precursor to a lawsuit. His family is represented by attorney John Burris, who has sued the city over several other fatal police shootings, including the Dec. 2 death of Mario Woods.Gongora died at a homeless encampment in the Mission District, where he had allegedly lunged at officers while wielding a kitchen knife. His family's attorneys say that surveillance footage of the incident, first obtained by the, show one of the police officers who fired a fatal shot aiming a shotgun towards the ground."They shot him to pieces," attorney Adante Pointer told the. "It's ridiculous." Gongora lived in one of the Mission District's many tents. He kept in contact with his family, who lived in Mexico's Yucatan peninsula, some of whom were on hand for a press conference in San Francisco on Friday.Police responded to the camp where Gongora lived after homeless outreach workers called 911 to report a man with a knife.According to police, Gongora died after he lunged at officers, who had fired beanbag rounds at him in an attempt to stun or disable him. Eyewitnesses have disputed the account. The encounter took about 30 seconds, as thefirst reported.An investigation into the shooting is not expected to be released for months.An investigation by the San Francisco District Attorney's office into the shooting of Amilcar Perez-Lopez, who was shot in the back by police on Folsom Street last summer, has yet to be concluded.