Derek Chauvin, a White former Minneapolis police officer convicted of the murder of George Floyd, pleaded guilty on Wednesday in a federal court in Minnesota to separate charges that he violated Floyd’s civil rights during the Black man’s murder, reversing his not-guilty plea in September, according to media reports. 

Chauvin, 45, entered his guilty plea in US District Court in St Paul, Minnesota. Prosecutors asked the judge to sentence Chauvin to 25 years in prison, which would run concurrent to his 22.5-year state sentence for George Floyd’s murder, adding on about two years, The New York Times reported.

It was the first time that Chauvin, who is appealing his murder conviction, admitted guilt for holding his knee to Floyd’s neck for nearly 10 minutes until Floyd died, in a case that sparked nationwide Black Lives Matter protests against police abuse. 

Chauvin was sentenced in June for Floyd’s 2020 murder, which was captured by a bystander on her cellphone.

His conviction in state court on charges of unintentional second-degree murder, third-degree murder and manslaughter was seen by many as a landmark rebuke of the disproportionate use of police force against Black Americans, FRANCE24 reports.

The video that showed Chauvin kneeling on the neck of the handcuffed Floyd for more than nine minutes during the arrest caused global outrage — and triggered one of the biggest protest movements in the US in decades.

Chauvin and three other officers — Thomas Lane, J. Alexander Kueng and Tou Thao — were arresting Floyd on suspicion of using a fake $20 bill. Lane, Kueng and Thao face charges in a state trial scheduled to begin in March that they aided and abetted the killing of Floyd.

In addition to the state charges, all four officers were federally indicted in May on charges of depriving Floyd of his civil rights by failing to provide him with medical attention.

Chauvin also was federally charged with violating Floyd’s right to be free from unreasonable seizure and unreasonable force by a police officer. Thao and Kueng were federally charged with violating Floyd’s right to be free from unreasonable seizure by not intervening to stop Chauvin from kneeling on Floyd’s neck.

Chauvin had also pleaded not guilty to federal charges of violating the civil rights of a 14-year-old boy he arrested in 2017.