MONTREAL -- Montreal police responded to a call about a person who'd been stabbed in the upper body at around 11:40 p.m. on Monday night. 

According to preliminary information, two victims were in a park in the Villeray-Saint-Michel-Parc-Extension borough and were attacked with an irritant gas for an unknown reason. One of them -- an 18-year-old man -- was also stabbed with a sharp object.

The suspect -- or suspects -- then fled the scene, police say. 

The 18-year-old was taken to hospital to be treated for his injuries, which police say were not life-threatening. 

Investigators will analyze the scene in order to better understand the circumstances surrounding the event.