Two people have been critically injured.
Quebec provincial police have cordoned off a wide perimeter in a rural area, near the corner of Des Trente-six and Branche-du-Rapide roads.
Nearly a dozen squad cars and several ambulances were visible at the scene.
Members of the police force's tactical unit and canine unit were also on site.
A Sûreté du Québec spokesperson wouldn't offer further details, saying the police operation is ongoing.