Ugly scenes in the stands at BMO Field during Toronto FC's 2-1 loss to rival CF Montreal in Canadian Championship play Tuesday prompted an investigation by TFC officials and condemnation from Montreal.

Toronto, which has hoisted the Voyageurs Cup eight times and finished runner-up five times, exited at the first hurdle this year after getting a bye to the preliminary round as 2022 runner-up.

The game was marred by several episodes in the stands, captured in video posted on social media.

There were fights involving some travelling Montreal fans, in their perch in the north corner of the east stand. One video showed some eight people brawling at the top of the stand.

"Hey @TorontoFC, you knew we were coming to the game, you told us there would be security. They came directly at us. You let this happen. Fire the whole security department," tweeted a fan, who goes by the handle Ethan.

Montreal issued a statement Wednesday, calling the incidents "unfortunate and unacceptable."

"CF Montreal condemns all acts of violence, and an investigation is underway," the statement added. "The safety of our fans and supporter groups is of paramount importance to the club. No violence of any kind is tolerated at Stade Saputo, nor at any other stadium to which our fans travel.

"We have consequently made the decision to close the visiting supporters’ section at Stade Saputo for Saturday's (league) game against Toronto. TFC fans who purchased tickets in this section will be refunded. We are in discussion with Canada Soccer, Major League Soccer and Toronto FC to ensure that all future events take place in a safe and secure environment."

Montreal coach Hernan Losada made mention of the violence in his post-match availability.

"I saw a group of fans today coming all the way from Montreal to support us. Unfortunately I heard there were some incidents in the stands," the Argentine said. "I hope they are all well, because their support is very important for us."

Following the final whistle, Toronto midfielder Mark-Anthony Kaye had to be restrained on the field from going after some abusive TFC fans in the south stand. Video posted on social media showed a fan throwing a megaphone on the field in Kaye's direction.

Some supporters groups in the south stand have leaders with megaphones who orchestrate chants.

Kings in the North, one of the supporters groups, put out a statement after the game distancing themselves from the incident.

"The events tonight involving another section's capo (leader) and Kaye is frankly unacceptable. We have no tolerance for this absolute garbage. We have the utmost respect and loyalty for the team. 'For all the highs and lows.' This is the mantra we sing and it means everything. There is absolutely no place for this filth in our stands."

The performance on and off the field drew plenty of social media comment, including calls for Toronto front-office firings.

"Fights in the stands. A megaphone thrown at players. Bad football. What happened to our club?" tweeted a fan under the handle TFC Forever.

Attendance for Tuesday's was announced at 17,726, down from 27,438 for the weekend league loss to New England. The Canadian Championship game was part of the TFC season ticket-holder package,

It's been a tough couple of years since TFC's run of success ended in a loss to the Seattle Sounders in the 2019 MLS Cup final, Toronto's third trip to the championship game in four years (the club lost to Seattle in the 2016 final and beat the Sounders in 2017).

Toronto finished second in the Supporters' Shield standings in the pandemic-affected 2020 season at 13-5-5 but was upset by Nashville in the first round of the playoffs, prompting coach Greg Vanney to step down. He is now coaching the Los Angeles Galaxy.

TFC has gone 17-39-23 since in league play, missing the playoffs after finishing 26th and 27th overall in 2021 and '22. Toronto (2-3-6) currently stands 22nd in the overall standings.

Chris Armas, Vanney's successor was fired in July 2021 after a 1-8-2 start to the season. Javier Perez finished out the 6-18-10 campaign but was not retained.

Bob Bradley, a three-time MLS coach of the year, took charge of TFC as head coach and sporting director after the 2021 season.

Toronto dug deep into its pocket to sign Italian stars Lorenzo Insigne and Federico Bernardeschi, who made their MLS debut midway through last season. But injuries and a lack of depth have frustrated the team this year.