The incident was said to have happened Thursday in the prison’s outdoor recreation area. A shank is believed to have been used.
The extent of Butt’s injuries are unknown, but they are not believed to be life-threatening.
The RNC is investigating the incident, but no charges have been laid.
Butt made headlines last year when he allegedly killed his young daughter.
He has pleaded not guilty to first-degree murder and arson in relation to the death of his daughter Quinn, who was five years old. Butt and Quinn were found inside his burning home on Hayden Heights in Carbonear on April 24, 2016.
Butt has been in custody since then.
His trial is set for 2018.