According to a media report, former US sports doctor Larry Nassar, convicted of mass sexual abuse, was stabbed during an altercation with another prisoner. The incident happened on Sunday in a prison in the state of Florida, the AP news agency reported on Monday, citing unnamed sources.

Nassar suffered stab wounds to his back and chest. His condition is stable, ABC also reported. The US broadcaster spoke of a night attack on Nassar.

The US prison authorities said on request that an inmate was attacked on Sunday afternoon and then taken to a hospital. The authority did not provide information on the identity of the attacked, citing the privacy of the detainees and security reasons. No prison officials or other detainees were injured in the incident. The incident is now being investigated internally.

The longtime doctor at the US Gymnastics Federation had sexually abused numerous young gymnasts. He had been convicted of sexual assault in more than 250 counts in three judgments with sentences totaling up to 175 years in prison. More than 150 girls and women were heard in the process, including several Olympic champions such as world star Simone Biles Owens.

Nassar pleaded guilty in November 2017. Rachael Denhollander, the first woman to publicly accuse the doctor, said after the verdict: “It’s over. Almost six years after I filed a complaint, it’s finally over.” Nassar’s victims were awarded hundreds of millions of dollars in damages as a result of the investigation and trial.