Investigators are reporting the fire was intentionally set at 539 Church St. in Windsor on Wednesday night.
Damage is pegged at $100,000.
An investigator with the office of the Ontario Fire Marshal attended the scene.
Two people were injured in the blaze, which broke out around 10:30pm on Wednesday. A third person was rescued from an attic apartment.
Windsor police have laid arson-related charged against two men in connection with the fire at 539 Church St.
The fire happened just three doors down from a suspicious fire Tuesday night.
- with files from Jason Viau and Kevin Black