September 1 - An arson attack on the Blue Bird Café in Montreal kills 37 and leads to nationwide changes to fire codes.
September 4 – Armed robbers steal 18 paintings, including a Rembrandt, along with 38 pieces of jewellery, from the Montreal Museum of Fine Arts, valued at $2 million at the time in what is not only Canada's largest art theft but its largest theft of private property ever. Except for one returned in an attempt to negotiate a ransom, none of the paintings have been recovered nor have the thieves ever been identified publicly.