A 19-year-old man was repeatedly punched and forced to remove his clothes at a city nightclub.
The victim needed hospital treatment after suffering a bloody nose and bruising to his face at the Cookies and Cream Nightclub in Savoy Crescent.
He has now been discharged from hospital after the incident, which happened between 1.45am and 2.10am on Monday.
The offender is an Asian man, approximately 6ft 2ins and was wearing a black coat and smart clothing.
Investigating officer PC James Clarke from Milton Keynes police station said: “I am appealing to anyone who might be able to identify the offender to come forward.
“I would also like to speak to anyone who saw the victim being taken to the fire exit, or who saw the victim after he had been stripped of his clothing in the club.
“The club was open at the time of the offence and it was the early hours of the Bank Holiday so I would expect there could be a number of potential witnesses who saw this incident occur.”
A 34-year-old man from Wellingborough was arrested on Monday on suspicion of assault occasioning actual bodily harm and bailed until July 2.
Anyone with information should contact PC James Clarke via the Thames Valley Police Enquiry Centre on 101.
If you don’t want to speak directly to the police, you can contact the independent charity Crimestoppers anonymously on 0800 555 111.
No personal details are taken, information is not traced or recorded and you will not go to court.