A lone woman was dragged to the floor sexually assaulted and robbed by a gang of men.
Police are appealing for witnesses after the incident in the Kemp Town area of Brighton on Sunday April 20.
The 45-year-old was on a night out, in the city when she became lost and found herself in the area at about midnight.
As she walked she turned into a road that was a dead end and heard voices behind her. Four men then attacked her dragged her to the floor and sexually assaulted her.
The victim tried to fight them off but they took her bag and fled. The woman then flagged down a police van in East Street.
Detective Constable Kerri Bartup said: "It must have been a terrifying experience for the victim. She found herself lost and at the mercy of a gang of violent men who took advantage of the fact she was on her own.
"This was a horrific crime and I want to speak to anyone who might have any information that could help, such as anyone who recognises the description of the offenders.
"We are still not certain exactly where the attack happened but believe it was someone close to where the victim spoke to the officers in East Street.
"If you know anything at all, no matter how little, please contact us."
All of the men were white, aged 17 to 23 and wearing jeans and trainers.
The first man was 5' 4" to 5' 6" and was wearing a dark hooded top.
The second man was 6ft and was wearing a Nike sweatshirt.
The third man was 6ft, had a big nose and was wearing a dark hooded top. The fourth man, who was also 6ft, was wearing a dark hooded top.
Anyone with information should call 101 quoting serial 204 of 20/4, email firstname.lastname@example.org or call the independent charity Crimestoppers anonymously on 0800 555111.