Firefighters were called to an address on Port Royal Trail, near Brimley Road and Steeles Avenue East, at 4:25 p.m. ET.
Initial reports suggested that a second house has been damaged, but firefighters say that up to four homes may have been damaged.
Firefighters say they are trying to remove people from debris at the scene.
Initial reports indicated a woman was without vital signs. However, paramedics said that a 50-year-old man has died.
The fire marshal is en route to the scene.
More to come