Former USA Gymnastics doctor Larry Nassar was assaulted during an incident at the federal prison where he is housed in Florida, according to two sources familiar with the incident.

Joe Rojas, president of the local correction officers’ union, tells CNN that Nassar was stabbed a total of 10 times, twice in the neck, twice in the back, and six times in the chest. Rojas credits corrections officers on the scene with saving Nassar’s life. Rojas says Nassar is in stable condition.

A statement from the Bureau of Prisons confirms, “on Sunday, July 9, 2023, at approximately 2:35 pm, an inmate was assaulted at the United States Penitentiary (USP) Coleman II, in Sumterville, Florida. Responding staff immediately initiated life-saving measures. Staff requested Emergency Medical Services (EMS) and life-saving efforts continued.”

An internal investigation into the incident is underway, the statement says. The inmate, who a source familiar confirmed is Nassar, was transported to a hospital for treatment.