The incident happened on Tuesday, July 5 at 22:25
According to police, a man was riding the subway eastbound when he committed an “indecent act” in front of another passenger.
The man got off the train at Warden station and ran away.
He is described as 18 to 25 years old and six feet tall with a thin build.
The suspect was last seen wearing a gray zip-up hoodie, green pants, white shoes, a black face mask and black sunglasses and carrying a green backpack.
Anyone with information should contact Toronto police at 416-808-4100 or Crime Stoppers anonymously at 416-222-8477 (TIPS) or www.222tips.com.