Sgt. Robert Shawinsky said the incident took place Monday night at the Sign of the Whale when a woman bumped into Lilijana Memlia, 26, of the Bronx.
Shawinsky said Memlia punched the woman in the face after the victim apologized for bumping into her.
An off-duty police officer working security broke up the fight and tried to calm everyone down, Shawinsky said.
After identifying himself as an off-duty cop and trying to escort Memlia out of the bar, she hauled off and hit him in the jaw, Shawinsky said.
Memlia was charged with assault on a police officer and assault.
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