A private autopsy has found that George Floyd died of asphyxiation from sustained pressure, CNN reports.

According to the autopsy, Floyd experienced a lack of blood flow to the brain caused by compression to his neck and back. Videos show that white police officer Derek Chauvin forcibly held his knee on Floyd's neck for eight minutes and 46 seconds, while other officers knelt on his back. Chauvin continued to apply pressure two minutes and 53 seconds after Floyd was unresponsive.

Ben Crump, attorney for the Floyd family, revealed that Floyd was essentially "dead on the scene" in Minneapolis on May 25. "The ambulance was his hearse," Crump said on Monday. "George died because he needed a breath. He needed a breath of air."

Dr. Michael Baden, one of the independent medical examiners, weighed in by saying, "There is no other health issue that could cause or contribute to the death. Police have this false impression that if you can talk, you can breathe. That's not true."

Death by asphyxiation is considered a homicide, which is the death of a person caused by another person. Previously, however, Chauvin was charged with third-degree murder and second-degree manslaughter following preliminary autopsy results. Crump now insists Chauvin should be charged with first-degree murder.

Floyd's cause of death is currently being investigated by local, state, and federal law enforcement, as the cause and manner of his death remains pending. For more on the independent autopsy findings, visit CNN.

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