The video shows the suspect exiting the subway at Seventh Avenue and 14th Street in Chelsea.
The suspect allegedly stabbed a man several times in that station around 6:15 p.m.
The suspect is thought to be in his 40s and between 5-foot-7 and 5-foot-9. He was last seen wearing a light blue striped shirt and dark pants.
Police did not say how badly the 28-year-old victim was hurt.
Anyone with information in regards to this incident is asked to call Crime stoppers at 1-800-577-TIPS (8477).
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