I had just moved downtown that August and the strike occurred on the 8th. of October. From CBC archives:

Montreal's 'night of terror'

Broadcast Date: Oct. 8, 1969
Montreal is in a state of shock. A police officer is dead and 108 people have been arrested following 16 hours of chaos during which police and firefighters refused to work. At first, the strike's impact was limited to more bank robberies than normal. But as night fell, a taxi drivers' union seized upon the police absence to violently protest a competitor's exclusive right to airport pickups. The result, according to this CBC Television special, was a "night of terror."

Shattered shop windows and a trail of broken glass are evidence of looting that erupted in the downtown core. With no one to stop them, students and separatists joined the rampage. Shop owners, some of them armed, struggled to fend off looters. Restaurants and hotels were also targeted. A corporal with the Quebec provincial police was shot and killed at the garage of the Murray Hill limousine company as taxi drivers tried to burn it down.

As police returned to duty in the wee hours, the arrests began. By morning, the city's public buildings were under guard by the army, which was summoned by Premier Jean-Jacques Bertrand. At least 20 people have been injured, and damage from the riot has been estimated at $2 million ($10.7 million in 2005 dollars).