A stubborn fire that destroyed a boarded-up heritage building in downtown Toronto continued to occasionally flare on Tuesday morning, as investigators attempted to determine what caused the blaze.
An aerial tower dumped water on the remains of 335 Yonge Street, just north of Dundas Street, for about 15 minutes Tuesday morning after a six-alarm fire gutted the building one day earlier.
Traces of smoke continued to waft from the rubble. Officials have said that the building's roof fell inward and perhaps blocked heat pockets from being doused during Monday's battle.
‘There still are working fire conditions in there in some spots. Until you see the roof and stuff get lifted off, you are probably going to see the same kinds of conditions," investigator Mike Ross of the Ontario Fire Marshal's Office told reporters on Tuesday.
About 125 firefighters were called to the site, near the corner of the Ryerson University campus, shortly after 4 a.m. Monday to battle a blaze that is believed to have started on the building's second or third floor.
Two firefighters slipped and fell into the fire while standing on an adjacent rooftop. The two men and another firefighter were taken to hospital with minor injuries.
Investigators on site Tuesday were preparing to sift through about three metres of debris to attempt to determine what caused the fire.
Ross said it was too early to determine whether the fire was started deliberately.
Coun. Kristyn Wong-Tam (Ward 27, Toronto Centre-Rosedale) told reporters on Monday that power, gas, hydro and water had been shut down in the building, which has sat empty since an exterior brick facade collapsed in April.
She said a security fence around the site made it unlikely that squatters had been inside.
Ross said he had spoken to the site's owners but had not conducted a full interview. "What is in there is what is key for us in the investigation," he said.
He said subway grates will have to be blocked and they will have to be sure the site will not collapse further before investigators enter the site. Air monitors will be used to determine whether asbestos was in the century-old building, and whether any was released in the collapse.
Yonge Street remained closed to traffic Tuesday morning. Officials say businesses should be able to open as usual on the west side of Yonge Street on Tuesday. But businesses on the east side near the fire site might still be closed.
Ryerson University resumed classes Tuesday.
