The SPVM has tweeted out repeated warnings to Montreal residents as May Day anti-capitalist protests sweep the city.
While the police had alerted residents to possible traffic disruptions earlier in the afternoon, reports of illegal activity prompted authorities to order protestors to disperse.
There are currently ongoing police interventions in the neighbourhood of St-Henri. An eye-witness also tells MTLBlog that a police intervention has occurred downtown on rue Ste-Catherine, though the SPVM has not confirmed any activity there on its Twitter account.
The police gave several warnings on social media before dispatching officers in riot gear.
Rues St-Antoine and Atwater converge just south of the route 720 overpass between St-Henri and Westmount.
Photos shared with MTLBlog by Instagram user caprikaren capture at least one fire downtown.
A video posted to Twitter shows massive police activity near Lionel-Groulx STM metro station.
May Day, or International Workers' Day, has long been an occasion for people to stage anti-capitalist demonstrations around the world.
Raucous protests and the subsequent intervetion of police forces are not unheard of on May Day in Montreal.
Stay tuned for updates on this developing story.