A male victim who was being chased in the downtown core has been taken to hospital in life-threatening condition after being stabbed.
The incident took place in the area of Yonge and Wellesley streets at around 8 p.m. on Monday.
Officers responded to a report of a group of men chasing a man in the area.
Upon arrival at the scene, police located a male victim suffering from a serious stab wound.
He was subsequently taken to hospital to be treated for his serious injuries, Toronto Paramedics said.
Investigators said a group of suspects fled the scene following the incident and described them as white males in their 20s.
Roads have been closed in the area to accommodate a police investigation.