US | Sports doctor Larry Nassar stabbed multiple times at Florida federal prison

The people were not authorised to publicly discuss details of the attack or the ongoing investigation and spoke to The Associated Press on the condition of anonymity.

Nassar was sentenced to decades in prison for sexually assaulting gymnasts, including Olympic medalists.

Nassar is serving decades in prison for convictions in state and federal courts. He admitted sexually assaulting athletes when he worked at Michigan State University and USA Gymnastics, which trains Olympians. Separately, Nassar pleaded guilty to possessing child pornography.

During victim impact statements in 2018, several athletes testified that over the course of Nassar's more than two decades of sexual abuse they had told adults what was happening, including coaches and athletic trainers, but that it went unreported.