Stephon Clark, the 22-year-old black man shot and killed by Sacramento police earlier this month, was shot eight times, six in the back, an independent autopsy commissioned by Clark's family found.

The results were released at a Friday news conference by forensic pathologist Dr. Bennet Omalu, who conducted the autopsy.

The first wound was to Clark's side, which led Dr. Omalu to conclude Clark was facing the house when he was first shot. Six other shots hit him from behind and one in the thigh. The Sacramento Police Department has said Clark was shot at 20 times.

Family lawyer Benjamin Crump said the findings of the family's autopsy contradict the narrative put forth by the Sacramento Police Department.

Sacramento Police initially said "officers believed the suspect [Clark] was pointing a firearm at them." Sacramento Police has not yet responded to the autopsy findings.

"Prior to the shooting, the involved officers saw the suspect facing them, advance forward with his arms extended, and holding an object in his hands," Sacramento Police said in a release a few days after the shooting, "At the time of the shooting, the officers believed the suspect was pointing a firearm at them. After an exhaustive search, scene investigators did not locate any firearms. The only items found near the suspect was a cell phone."

Dr. Omalu, who is most well known for his brain injury research, pointed at diagrams of Clark's wounds as he spoke.

Each one of the bullets "possessed a fatal capacity," Dr. Omalu said.

Death was "not instantaneous," Dr. Omalu said, adding that his results suggest Clark lived for 3-10 minutes before he died. One question hanging over the case is whether officers got him medical attention quickly enough to be saved.

It's unclear whether the wounds into his back occurred while he was upright or once he was on the ground.

The official coroner's autopsy has not yet been released.

Funeral services for Clark were held Thursday and attended by the city's mayor, and Rev. Al Sharpton.

The city has experienced nearly two weeks of protests since the shooting. This week, activists have blocked thousands of fans from entering Sacramento Kings games and hundreds attended a boisterous community forum at City Hall, as Capital Public Radio reported .

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