Thousands rushed to the streets for initially peaceful celebrations following the Montreal Canadiens' seventh-game win over the Boston Bruins, which advances Montreal to the next round of the NHL playoffs.
The jubilation degenerated into mayhem around midnight, however, as hockey fans spilled onto the streets.
"It started pretty well," police spokesman Const. Laurent Gingras told CBC News Tuesday.
"Unfortunately, at a certain point some people gathered on Ste. Catherine Street. A couple fights broke out and police cars were also attacked at that point."
A few hundred people, some intoxicated, marched down the downtown avenue, throwing rocks and bottles at police and torching vehicles, the CBC's Steve Rukavina reported from Montreal.
16 police cars damaged
Despite increased police presence deployed to the streets before Monday night's game, rioters burnt or smashed 16 police cars and at least five other vehicles.
At least five businesses were ransacked as well, although Gingras said the damage was limited.
"One minute we were all hanging out and celebrating and then all hell broke out," said Jean-François Hotte, who watched as a Foot Locker store was ransacked by looters. A liquor store was also hit.
"It didn't take five minutes before everyone was up on Ste. Catherine Street. It went really fast."
City police, backed up by riot squad officers, used pepper spray and batons to quell the crowd, which dispersed around 2 a.m. There were no reports of serious injuries.
Gingras said it was not immediately clear if the rioters were just rowdy fans or others who "used the occasion to do their mischief." At least 16 people were detained, including one minor, Gingras said. Possible charges include break-and-enter, mischief against a police vehicle, assault against a police officer and numerous municipal bylaw violations.
A similar riot after a Stanley Cup victory in 1993 caused major damage.
Gingras said that while the investigation is continuing, large numbers of police will be present before, during and after upcoming hockey matches at the Canadiens' home arena, the Bell Centre.
With files from the Canadian Press