Three men have been arrested by police officers investigating reports of a rape at The Level in Brighton.
The incident is alleged to have taken place between 12.30am to 1.30am on Friday, September 16.
A 47-year-old man has been arrested on suspicion of rape.
A 19-year-old man and a 20-year-old man has been arrested on suspicion of conspiracy to rape.
More police are on patrol in the area and the victim is receiving support from specially-trained officers.
Anyone who may have seen something suspicious in the area at the time is being asked to contact Sussex Police and quote Operation Motto.