It happened Thursday night at the Brentwood station.
The MTA says he got into a fight with the conductor on the Penn Station-bound train when he was trying to collect the fare.READ MORE: Funeral Today For Probationary Firefighter Vincent Malveaux
The suspect allegedly pulled out a folded pocket knife then escaped through an emergency window.
The man did not unfold the pocket knife, according to officials.
The investigation is ongoing.MORE NEWS: New Sharks Exhibit Coming To American Museum Of Natural History
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