Investigators say the man grabbed a woman's bag on the stairway at the Crescent Street J train station in Cypress Hills.
The incident happened just before 6:30 p.m. on August 30.
The suspect got away.
The victim was not hurt.
The suspect is described as a Hispanic male, approximately 15 to 18 years old. He is about 5-foot-8 and 160 pounds, and he was last seen wearing a white T-shirt, dark shorts, a black baseball cap and a black book bag.
Anyone with information in regards is asked to call Crime Stoppers at 1-800-577-TIPS (8477).
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