NBC reports that Derek Chauvin has been returned to prison custody after the former Minneapolis police officer was attacked by a fellow inmate. On November 24, Chauvin was stabbed 22 times with an “improvised knife” while he was in the Federal Correctional Institution of Tucson, Arizona’s law library. According to a criminal complaint, Chauvin was attacked by fellow inmate John Turscak.

Chavin’s attorney released a statement on December 3 saying that Chauvin’s , “medical condition has improved to the extent that he has been removed from the trauma care facility at a local Tucson hospital and returned to prison custody for his follow up care.”

His family is very concerned about the facility’s capacity to protect Derek from further harm. They remain unassured that any changes have been made to the faulty procedures that allowed Derek’s attack to occur in the first place, Gregory M. Erickson, Derek Chauvin’s attorney, via NBC.

NBC reports that the 52-year-old Turscak has been charged with attempted murder, assault with intent to commit murder, and assault with a dangerous weapon. Federal prosecutors said that Turscak has also been charged with assault resulting in serious bodily injury in connection with the stabbing.

According to prosecutors, Turscak said he chose “Black Friday” to attack Chauvin as a symbol for the Black Lives Matter movement. NBC reports that Chauvin is serving a sentence of over 22 years for the killing of George Floyd.

The former Minneapolis police officer is also simultaneously serving a 21-year federal sentence for violating Floyd’s civil rights. Chauvin is also serving a 22-and-a-half-year sentence for second-degree murder.