At around 0240hrs on Saturday 23 June, a 20-year-old man was dancing on the dance floor when a man, who was not known to him, is alleged to have assaulted him.
The man was taken to HRI for treatment and received a number of stitches to a cut above his eye.
Police arrested a 19-year-old man in connection with the incident. He has been bailed to a date in July pending further enquiries.
Anyone who may have witnessed the incident is asked to call Humberside Police tel 101 quoting crime reference 1914272.