It happened Monday, December 12 at 8:50 a.m. inside the Atlantic Avenue subway station.
The victim suffered a fractured left arm and wrist, cuts to his left knee, and bruising to his right knee.
He was taken by EMS to Methodist Hospital in stable condition.
The attacker fled on a northbound Q train in an unknown direction.
Anyone with information in regard to this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
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