A teenager was raped in the early hours of Sunday morning in Milton Keynes.
The 18-year-old was walking over a footbridge in Fishermead between 1am and 1.15am when she passed a group of four black men.
As she walked on towards Pencarrow Place, one of the men followed the girl and sexually assaulted her.
The offender is black and between 5ft 8in and 6ft tall. He was wearing baggy jeans.
Investigating officer, Det Ch Insp Vince Grey said: “I am appealing for anyone with any information to contact the police immediately.
“Did you see a group of black men near or on the footbridge over Childs Way in the early hours of this morning, did you see a young woman walking in the area at about 1am, did you see a black man and a woman together in Pencarrow Place, or did you hear a woman in distress at this location? If you did please contact police via 101.
“Alternatively, if you don’t feel comfortable speaking to police you can call Crimestoppers anonymously on 0800 555 111 or online at www.crimestoppers-uk.org.
“No personal details are taken, information is not traced or recorded and you will not go to court.
“I would like to reassure the community in Milton Keynes that this is an isolated incident and that a thorough investigation is underway.”
If you have any information please contact the Thames Valley Police Enquiry Centre on 101 and quote URN 555 of August 4.