A correctional officer at a medium-security prison in Ontario suffered a suspected concussion and bruises after he was ambushed by a prisoner today in a violent attack on a cellblock. Corrections Canada isn’t providing much detail about the incident, perhaps in a bid to downplay the seriousness of the assault, but Cancrime learned that an inmate attacked the Collins Bay Institution officer from behind with a blunt weapon, smashing him first on the head and neck. As the officer tumbled to floor and desperately reached for his pepper spray, the inmate continued the attack, sources told me.