Some 15 people were taken to the hospital after the blast at the Bombay Bhel restaurant. Three people had critical injuries, the Peel Regional Paramedic Service said in a Tweet.
The blast occurred just after 10:30 p.m., media reported. There was no word on the cause.
The blast comes a month after a driver plowed his white Ryder rental van into a lunch-hour crowd in Toronto, killing 10 people and injuring 15.
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