It happened over the weekend at Food Universe on East 194th Street in the Fordham Manor section of the Bronx.
The store manager declined to appear on camera, but said video of the incident tells the story.
The women descend on the cashier, who is seen in the video wearing a white down vest. She is shoved and punched repeatedly, even as the cashier's fellow employees try to break it up.
The manager says the woman became enraged after she had returned bottles and was forced to wait on line to cash them in.
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The cashier was traumatized, but not badly injured. She was later treated at a nearby hospital and is recovering at home.
The incident happened on Sunday afternoon, although the dispute allegedly took place several days earlier.
Police do have good images of the suspect and her accomplices.
Store employees say the woman is a regular at the supermarket. They have seen her before, but no one has been arrested, at least not so far.
The store owner is offering a $2,500 reward for information that leads to arrests.
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