Officers were called to reports that four women had punched another woman in Portobello Street at about 9.45pm on September 4, before kicking her while she was on the ground.
The 19-year-old victim was taken to hospital with a suspected broken rib, hand injuries and facial injuries.
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A spokesperson for Humberside Police said: "Did you see what happened? Do you have any information that you can give us? Contact us quoting reference 16/93699/18."