An early-morning fire that broke out in a Toronto restaurant caused about $300,000 in damage, fire officials say.

Investigators are looking into the cause of the two-alarm blaze, which occurred at 1239 St. Clair Ave. W., at Via Italia, shortly after midnight.

The restaurant was closed at the time.

When firefighters arrived, the two-storey building’s smoke alarms were sounding and smoke was visible inside. After crews forced their way into the building, they encountered "heavy fire" in the kitchen/serving area behind the bar.

Flames had spread from the basement to other floors but crews managed to prevent the blaze from spreading to neighbouring properties, a fire official said.

The building was not protected with a fire sprinkler system.

While exiting the restaurant, a firefighter twisted his ankle when he slipped on some plate glass. He was taken to Toronto Western Hospital, where he was treated and released shortly after 2 a.m.

No other injuries were reported.

Investigators believe the fire originated in an electrical room. The Office of the Fire Marshal is investigating the cause.

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