BROOKLYN - The NYPD is looking for a man who allegedly struck a commuter in the head with a hammer during a subway robbery. 

According to police, the 32-year-old victim was trying to buy a MetroCard at the Fulton Street and Rockaway Avenue train stop in Brownsville Wednesday morning when he was attacked from behind.

They say the man demanded cash, which the victim handed over. The victim was then treated and released from Brookdale Hospital for his head injury. 

Investigators released surveillance images of the suspect, who is described as a black man, about 5 feet 10 inches tall and around 140 pounds.