MINNEAPOLIS (AP) — The attorney for George Floyd's family planned to announce the findings Monday of an independent autopsy into his death after a Minneapolis police officer held his knee on Floyd’s neck for several minutes.

Floyd, a black man who was in handcuffs at the time, died after the white officer ignored bystander shouts to get off him and Floyd's cries that he couldn't breathe. His death, captured on citizen video, sparked days of protests in Minneapolis that have spread to cities around America.

According to prosecutors, preliminary findings from an official autopsy last week said the combined effects of being restrained, potential intoxicants in Floyd’s system and his underlying health issues, including heart disease, likely contributed to his death. There were no other details about intoxicants, and toxicology results can take weeks. In the 911 call that drew police, the caller described the man suspected of paying with counterfeit money as “awfully drunk and he’s not in control of himself.”

The criminal complaint said the autopsy “revealed no physical findings that support a diagnosis of traumatic asphyxia or strangulation.”

Ben Crump, the attorney representing Floyd's family, said last week that he was commissioning the family's own autopsy. Floyd’s family, like the families of other black men killed by police, wanted an independent look because they didn’t trust local authorities to produce an unbiased autopsy.

The family's autopsy was conducted by Michael Baden and Allecia Wilson. Baden is the former chief medical examiner of New York City, who was hired to conduct an autopsy of Eric Garner, a black man who died in 2014 after New York police placed him in a chokehold and he pleaded that he could not breathe.

Baden also conducted an independent autopsy of Michael Brown, an 18-year-old shot by police in Ferguson, Missouri. He said Brown's autopsy, requested by the teen's family, didn’t reveal signs of a struggle, casting doubt on a claim by police that a struggle between Brown and the officer led to the shooting.

The officer who held his knee on Floyd's neck, Derek Chauvin, has been charged with third-degree murder and manslaughter and is in custody in a state prison. The other three officers on scene, like Chauvin, were fired the day after the incident but have not been charged.

The head of the Minneapolis police union said in a letter to members that the officers were fired without due process and labor attorneys are fighting for their jobs. Lt. Bob Kroll, the union president, also criticized city leadership, saying a lack of support is to blame for the days of sometimes violent protests.

When asked to respond, Mayor Jacob Frey said: “For a man who complains so frequently about a lack of community trust and support for the police department, Bob Kroll remains shockingly indifferent to his role in undermining that trust and support." Frey said Kroll's opposition to reform and lack of empathy for the community has undermined trust in the police.

Gov. Tim Walz announced Sunday that Attorney General Keith Ellison would take the lead in any prosecutions in Floyd's death. Local civil rights activists have said Hennepin County Attorney Mike Freeman doesn't have the trust of the black community. They have protested outside his house, and pressed him to charge the other three officers.

Freeman remains on the case.