Unbeknownst to the group of four heroes, who had most likely just saved the city from a massacre beyond anything it had ever seen, a young adult with a camera caught everything on tape.
The man had been hiking and had inadvertently wandered close to the hospital's private grounds. So when the fight moved outside and into the forest, they almost swept the man into the conflict.
Luckily for him, the combat stopped moving close to him, and he got his phone out to record the whole thing. The man almost thought for a moment that a superhero movie was being filmed with a new generation of VFX.
Once he had caught everything on camera, he hurriedly walked away from there, not wanting to get caught filming a movie as it was being filmed. The fines for that were enormous, and he was way too broke to pay those.
As he fled the scene, the man opened the news, to see if anyone had heard about a movie being filmed in Montreal, to see what set he had stepped on.