Two young women were the subject of a sexual assault in the centre of Brighton.
They are believed to have been touched up by a man and to have shouted at him and his friend after the groping incident.
A woman passer-by broke up the confrontation.
The incident took place in the gardens opposite the Revenge night club in Old Steine, Brighton.
Sussex Police said that the two teenagers were badly shaken by the experience but were physically unhurt.
The women, both 18 and from West Sussex, were attacked just after 3.30am on Friday 8 October.
Detective Constable Laura Carron said: “We would like to speak to anyone who was in the area at the time and saw two women arguing with two men.
“We would particularly like to speak to a woman who separated the two groups and to other two girls who were sitting on a nearby bench and were also approached by the two men.”
Both men were described as of Middle Eastern appearance and of medium build.
One man was wearing a black and white horizontally striped top while the other man was wearing a black t-shirt with a large silver pattern on the front.
Anyone with information is asked to contact Sussex Police on 0845 6070999.
Two men, aged 19 and 20, from the Brighton and Hove area were arrested by police nearby shortly afterwards.
The first was arrested on suspicion of the assaults and the second on suspicion of threatening behaviour.
They were later released on police bail until Saturday 4 December while inquiries continue.