MONTREAL -- Montreal police are investigating an apparent fireworks mishap captured on video that shows an explosion in a crowd of Habs fans outside the Bell Centre Monday night.

Thousands of fans filled the streets of downtown Montreal to celebrate the Game 4 win against the Tampa Bay Lightningz, taking in a victory that saved the Canadiens from elimination from the Stanley Cup finals.

During the celebrations, fans set off several fireworks even as hundreds of police officers in riot gear patrolled the streets.

In one case, fans gathered in a circle around a firework that was lit when something goes wrong and it explodes into some of the fans.

Const. Raphael Bergeron said there were no reports of injuries from fireworks Monday night, but the dramatic incident was captured on video, which police will examine during their investigation. Police are also trying to find the person who lit the fireworks.

“It’s possible that charges could be laid,” said Bergeron. “The investigators are looking at possible images and what exactly happened, but at this moment I don't have further information.”

He said four people were arrested for criminal offences, including assault of a police officer.

It was a busy night for police, who also deployed tear gas to disperse the large crowds after the game -- a tactic police that has come under criticism by a Toronto human rights lawyer. 

The police service said tear gas necessary to reign in uncooperative fans who are said to have also thrown bottles in the post-game revelry.