Police say that a 19-year-old man was stabbed and called a cab, which took him to the Warden Avenue and Finch Avenue East area.
That man then called 911, and was taken to hospital. His injuries are not life-threatening, police say.
Police were informed about the stabbing at about 5:30 a.m. on Saturday, after the man had arrived at the hospital.
Investigators want to speak to the taxi driver, in part so they can trace back where the victim was picked up from.
The cab is described as a dark, late-model Chrysler 300 with a taxi sign on its roof. Police have released an image of the vehicle that dropped off the victim in Scarborough.
Anyone with information is asked to contact investigators at 416-808-4200.
Tips can also be passed on through Crime Stoppers at 416-222-8477.