Metro employees held an afternoon demo outside the STM's headquarters on de la Gauchetiere street in downtown Montreal Tuesday.
They are protesting cuts this summer to ticket agents, which they say will endanger the public.
The demo was noisy but peaceful, with around 100 union members taking part.
Union spokesman Tom Mouhteros says a lack of agents will increase the likelihood of accidents and crime.
"There's going to be no human presence," he said. "It's irresponsible for the STM to do something like this because these metro stations are not going to be secure at all."
He says agents are well trained to react in emergency situations and that their quick responsse can and have saved lives in the past.
He points to the incident last January at Fabre metro, when a woman was strangled to death when her scarf was caught in an escalator. No agent was on hand there.
Moutheros promises the protests will continue as long as their demands are not met. The cuts are to take effect in June.
Nine stations in total will be affected. They are du College, Plamondon, Place d'Armes and Henri-Bourassa on the organge line; de l'Eglise, Guy-Concordia, Peel, McGill and Place des Arts on the green line.