The video showed the woman being punched in the torso by a man who then follows her into the Ronkonkoma train station and drags her out. At one point he is seen shoving her and grabbing her by the hair.
The incident occurred on March 4. The footage was released Friday.
The MTA has declined to say if anyone has been arrested or characterize the couple's relationship.
They asked anyone with information about the incident to contact them at 718 361-2207.
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