Correctional Service Canada says an inmate has been injured in what it's calling a major assault at the Port-Cartier Institution located on Quebec's north shore.
The federal agency says the injured inmate was taken to hospital to receive treatment.
It says the assailant has been identified and the appropriate actions have been taken, but did not further specify.
Quebec provincial police are also investigating the alleged assault, which took place Sunday.
Correctional Service Canada says safety is its priority, and that it will review the circumstances surrounding the assault to prevent future incidents.
Port-Cartier Institution is a maximum-security federal prison located about 600 kilometres northeast of Quebec City.
