Huron County Ontario Provincial Police have deemed the Clinton fire an arson and have arrested and charged a 47-year-old man for his alleged involvement.
Investigators said they have reason to believe that the fire was set deliberately.
Ronald Davis of Central Huron has been charged with a string of offences including arson, disregard for human life and failing to comply with a probation order.
Officials said Albert Street between Huron Street and Rattenbury Street in Clinton will remain closed for the next couple of days.