Jeffrey Armstrong, 29, was last seen on April 8 at 3 p.m., in the Queen Street West and Ossington Avenue area.
He is described as black, five-foot, eight-inches tall, weighing 185 pounds, with black braided hair. He was last seen wearing what is described as a black "Ninja-style" outfit.
Police are concerned for his safety and the safety of the general public. He is considered dangerous and should not be approached by members of the public, police say. Please call 911 instead.
Anyone with information is asked to contact police at 416-808-1400 or Crime Stoppers at 416-222-TIPS (8477) or www.222tips.com.