Two men have been the victims of alleged sexual attacks after leaving the Heaven nightclub in Villiers Street, London.
The alleged attacks were said to have taken place in a car.
A man is in custody but police are now urging anyone else who has been a victim of a sexual attack in the area to come forward.
Detective inspector Jim Foley, of the Met Police’s Community Safety Unit, said: “We are concerned that they may not be isolated incidents and would like to hear from anyone who is concerned about being offered a lift home or being approached by an unlicensed mini cab.
“I would urge anyone who thinks they may have been a victim to come forward in confidence. We will work with you in a confidential and sensitive way and have specially trained officers who can support you and offer advice.
“Don’t suffer in silence. You will be taken seriously. I am interested in any information you may have – no matter how irrelevant you may think it is – so please call us.”
Men who think they may have been a victim, or anyone else with information, should call 020 7321 9434 as soon as possible or the anonymous Crimestoppers line on 0800 555 111.