Once on board, police allege the man immediately began acting aggressively and threatening other passengers.
The man then exited the streetcar before police arrived.
He is described as 20 to 30 years old, about five-foot-five with a medium build, short black hair, thick black bushy eyebrows and a goatee. He was last seen wearing black sunglasses, a black jacket, blue jeans and brown shoes.
Anyone with information is asked to contact police at (416) 808-1400 or Crime Stoppers anonymously at (416) 222-TIPS (8477).