MINNEAPOLIS - Derek Chauvin, the former Minneapolis police officer convicted over the death of Mr George Floyd, has been stabbed in federal prison and was seriously injured, the Associated Press said, citing a person familiar with the matter.

Mr Floyd’s death in 2020 unleashed a wave of protests worldwide against police brutality and racism after Chauvin, who is white, knelt on the handcuffed African-American’s neck for more than nine minutes in a murder caught on cellphone video.

The Federal Bureau of Prisons confirmed an unidentified inmate was assaulted at the Federal Correctional Institution in Tucson in Arizona, but declined to confirm if it was Chauvin.

Chauvin, 47, was stabbed by another inmate at the prison, the news agency said, citing a source who was not authorised to discuss the attack and sought anonymity.

The New York Times also reported Chauvin was stabbed, citing two people with knowledge of the matter.

In its statement, the bureau said employees of the medium-security prison responded to the attack and “initiated life-saving measures” for one individual, who was taken by emergency medical services to a hospital for treatment.

No employees were injured and the public was never in danger from the incident at 12.30pm MST. A bureau spokesperson said it would add no further information.

Mr Zach Graham, an attorney on the defence team at Chauvin’s trial, said the firm, Minneapolis-based Halberg Criminal Defence, had no comment on the reported stabbing.

A member of Chauvin’s appellate team, Mr Greg Erickson, said he had no knowledge of such an incident.

Chauvin is serving a 21-year federal sentence for violating Mr Floyd’s civil rights, and a concurrent term of 22½ years for murder on his conviction in the Minnesota state court.

On Nov 20, the United States Supreme Court declined to hear Chauvin’s appeal of his state court murder conviction.

The appeal was filed after a Minnesota appellate court upheld his 2021 murder conviction and rejected his request for a new trial.

Chauvin had said that jury bias and some rulings by the presiding judge deprived him of his right to a fair trial.

Chauvin was helping three fellow officers to arrest Mr Floyd in May 2020 on suspicion that he had used a fake US$20 (S$27) bill when buying cigarettes.

The three – Tou Thao, J. Alexander Keung and Thomas Lane – have been convicted of lesser state and federal charges. REUTERS