Knicks fans are no strangers to taking over arenas–even if it’s NOT their own. During last year’s first-round Sixers series, Philly’s Wells Fargo Center was flooded by thousands of passionate Knicks fans. There was more support for Jalen Brunson and Co. than for the actual home team. It even left Joel Embiid in shock: “I’ve never seen it, and I’ve been here for 10 years.” So, it comes as no surprise that the New York fanbase is bringing that same energy to Boston in the ongoing East Semis. But things might have gone a bit too far last night!

For the second straight game, the Knicks made a miraculous twenty-point comeback and beat the Celtics at home, taking a commanding 2-0 series lead. As expected, their fans were hyped after the win. But the situation escalated when some of them refused to leave TD Garden after the game. In a video that has since gone viral, several Knicks fans can be seen cheering and celebrating in the Celtics’ arena.

A woman, who was likely an usher, even attempted to control the chaos, but to no avail. The video shows her calling for security as she tries to stop a fan by putting an arena policy sign in front of his face. In the process, the woman unfortunately lost her balance and fell backwards onto the arena chairs. “HELP!” she screamed, calling out for security. After witnessing the entire incident, one security personnel came to her aid but took no significant action.

The woman pointed at the fan she was trying to stop earlier, seemingly blaming him for her fall: “He pushed me.” In response, the Knicks fan said, “It’s on camera. I didn’t touch her.” Well, the video clearly shows that the woman fell after stumbling on the stairs, and the accused fan did not push her. So, the security remained silent while Knicks fans continued the wild scenes with “Knicks in 4” chants.

Meanwhile, something far more chaotic was happening outside the arena.

Police intervene after ugly brawl breaks out in Boston between Knicks and Celtics fans

While some fans refused to leave TD Garden, others took over the streets of Boston after the Knicks’ epic win. The situation got out of hand when fans of both teams got into a heated physical altercation. In a late-night video from Boston’s Causeway Street, one Celtics fan wearing a Paul Pierce jersey could be seen bombarding a Knicks fan with several punches. As the camera pans, you see police trying to de-escalate the situation by asking the raging fans to “back up.”

One policeman even pinned a Knicks fan to the ground, potentially arresting him for his involvement in the ugly brawl. That did not stop the crowd from continuing the “Let’s go Knicks” chants.

Well, these are two of the most passionate NBA fan bases, and last night they proved why. Now, the series is heading to New York for the next two games, and it will be interesting to see how the Celtics respond in front of a hostile MSG crowd.