How will the STM react when it sees this video in the Montreal metro?

Lack of security in the Montreal metro? Reckless young people have decided to infiltrate the Montreal metro and have fun in the tunnels. We can see them in a machine room, on the rails having fun taking pictures with fireworks and moving around in the wagons as they want. He even taunts an employee by barring the door in front of her to escape afterwards. I don't know how the STM will react to this video, but safety must be paramount in the Montreal metro. (via the excellent Catherine brisson)

https://www.youtube.com/watch?v=jED_JBPsVbg

Update:

@gravelmatin It is above all dangerous and illegal. We are currently investigating this event.

- STM (@stm_nouvelles) March 29, 2016