Police say a fire broke out around 2:40 a.m. Monday morning at a clothing store on Henri-Bourassa Boulevard and Berri Street in Ahuntsic-Cartierville.
They say firefighters called police because one of the windows was shattered with a brick.
A Molotov cocktail was also found outside the business, according to police.
Police say one witness said they may have spotted a suspect.
No arrests have been made yet.