An altercation between a Hamilton Tiger-Cats fan and Toronto Argonauts players broke out and surfaced online Sunday night following the teams’ CFL semifinal game, including a sequence where one player punched the fan. Toronto Police are investigating the incident, according to Sportsnet, while a CFL spokesperson said the league is reviewing the incident.

The incident happened after the game when a group of Argonauts players — initiated by defensive back Chris Edwards — climbed over the railing from the field into the stands and waved over someone off-camera with his hand. The video panned to show at least three other Toronto players climbing over the railing, too.

Then, after a fan wearing a Tiger-Cats jersey shoved Edwards, he punched back and paired with wide receiver Dejon Brissett to shove the fan until he reached a wall that a security guard pinned him against.

Warning: Graphic Language

But the fight didn’t stop there. Heckling by fans continued as the rest of Toronto’s players entered what appeared to be a separate room, with one section of the metal gate falling when a team member dropped his bag and moved back toward fans behind the barriers.

The Tiger-Cats defeated the Argonauts, 27-19, and advanced to the Grey Cup, overcoming a 12-0 deficit early in the first half. They’ll face the Winnipeg Blue Bombers on Dec. 12 in the league’s championship.