As many as 85 Toronto firefighters battled a stubborn four-alarm blaze in a north Etobicoke auto garage Saturday night.

Toronto Fire Capt. Mike Strapko said they received multiple calls starting at 9:11 p.m. for reports of a car on fire inside A-1 Auto Repair on Kelfield Street, southeast of Highway 27 and Dixon Road.

Donny Bassaragh was on his way to work nearby when he came across the building engulfed in flames. He said the flames extended high over the roof of the building, and appeared "way out of control."

Fire crews began spraying the building eight minutes later. Twenty-one trucks are at the scene, firefighters said.

Platoon Chief Chris Bertram said they believe the fire started in the auto repair shop, and then spread to the rest of the building, which also houses a taxi company.

He said firefighters heard several explosions after they arrived, believed to be caused by propane tanks and other equipment inside the auto shop.

“It’s contained, it’s not getting any worse,” Bertram said. “But it’s stubborn because we can’t enter the building at the present time, so we’re pouring water on it from the exterior.”

Strapko said part of the building’s roof has collapsed, and firefighters are staying well back from its walls in case they collapse as well.

Bertram said he expects fire crews to be on scene all night, in order to conduct an investigation once all the flames are extinguished. No injuries have been reported.

The smoke plume caused by the inferno brushed up against a flight landing path for planes headed to Pearson International Airport, but Bertram said flights have been proceeding normally.