Two homes under construction on Minto Street in Leslieville were destroyed by a large fire early Thursday.
Fire crews were called to the scene just before 3 a.m.
Neighbours tell CBC News that work on the homes began earlier this year.
John Billings lives across the street and was awakened by the noise.
"I've never seen the enormity and burning embers like that in my life, it was like raining fire," he told CBC News. "The fire was at least three or four storeys high."
Patricia Martyn said she woke up after hearing glass shatter.
"As we looked out the window, it was just orange," she said. "[The fire] was coming over the houses across the street. It was pretty massive."
One man in his 80s had to be rescued from a home adjacent to the one where the fire is believed to have started.
There are no reports of injuries but two of the homes were completely destroyed. An adjacent house also suffered major damage. The fire was brought under control by firefighters by about 5 a.m.
The Ontario Fire Marshal is investigating.
Neighbours reported seeing some young people on the street prior to the fire and arson is being investigated as a possible cause.