Police are looking for a man caught on surveillance video ripping a chain off a woman's neck and tossing her to the ground at a Coney Island bus stop. 

The 54-year-old woman was standing at the stop on Mermaid Avenue and West 31st Street on July 18 when the man walked by and snatched the chain, causing the woman to fall face first to the sidewalk.

The suspect was seen passing by the stop several times before the theft.

A bystander is seen in the video (above) helping the woman. The suspect runs away, and at least one witness can be seen chasing after him.

The victim was treated at a nearby hospital for a cut to her head.

Anyone with information about the suspect is asked to call Crime Stoppers at 1-800-577-TIPS.