George Floyd died from asphyxiation while a Minneapolis police officer knelt on his neck, according to an independent autopsy ordered by Floyd’s family.

Floyd’s death last week while he was in police custody triggered nationwide, sometimes violent, protests that continued through the weekend.

In a statement, Floyd family attorney Ben Crump said the new autopsy “found the manner of Mr. Floyd’s death was homicide caused by asphyxia due to neck and back compression that led to a lack of blood flow to the brain.” During a news conference Dr. Michael Baden, who conducted the autopsy, talked about the findings (watch above).

That contradicted preliminary findings last week from the county medical examiner, who found “no physical findings that support a diagnosis of traumatic asphyxiation or strangulation.” But late Monday the medical examiner’s office altered that conclusion to match the new autopsy.

In his statement, Crump said the evidence indicates that Floyd died at the scene.

“For George Floyd, the ambulance was his hearse,” Crump said. “Beyond question, he would be alive today if not for the pressure applied to his neck by fired officer Derek Chauvin and the strain on his body from two additional officers kneeling on him.”

Crump said some of the officers taunted the handcuffed Floyd while holding him down.

Minneapolis Police Chief Medaria Arradondo said on Sunday that the four officers involved in Floyd’s arrest for allegedly trying to pass a counterfeit $20 bill were “complicit” in his death and should bear responsibility for it. All four officers were fired.

Now-former officer Derek Chauvin, whose knee was on Floyd’s neck for nearly 9 minutes, is in jail, charged with third degree murder and manslaughter. Floyd gasped that he couldn’t breathe, then passed out — but Chauvin stayed on his neck for almost 3 more minutes.

The other three officers involved may also face criminal charges.

There could also be federal charges; the FBI has joined the investigation of Floyd’s death.