Sergio Santiago, 41, threw an unknown object at the officer inside the Fordham Road subway station, causing a laceration. Officers had identified Santiago as a suspect in a stabbing earlier in the day. They chased Santiago for several blocks before losing sight of him.
Meanwhile, the injured officer was taken to SBH Health System and is expected to be OK.
Anyone with information is asked to call NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477).