Toronto police say that two men were approached by a third man at 1:50 a.m. in the Dundas Street East and George Street area.
Both victims were taken to hospital, where 36-year-old Rala Federick of Toronto died of his injuries. The surviving victim, a 37-year-old man, suffered non-life-threatening injuries.
Police are seeking a suspect described as a 20-to-30-year-old black male with a light complexion, who stands 5-10'' and has a heavy build.
Anyone with information is asked to contact investigators at 416-808-5100. Tips can also be passed through Crime Stoppers at 416-222-8477.