Police are asking for the public’s help in identifying the person who they say robbed a 14-year-old at knifepoint on an N train in Bensonhurst.

Investigators say the man pulled a knife on the boy at the 20th Avenue subway station and demanded his jacket on Jan. 22.

The man took the jacket and fled on foot in an unknown direction. The boy was uninjured.

Police urge anyone with additional information to call 1-800-577-TIPS.