A 19-year-old woman was sexually assaulted as she walked in Swindon.
The police have released a CCTV image of a man they want to speak to in connection with the assault, which happened at about 10.30pm on Thursday, 10 September.
A spokesperson said the woman was walking in the Greenbridge Retail Park/Greenbridge Road/Dorcan Way area of town when she was assaulted.
Just before the attack and while the victim was still alone, a car stopped and a woman in the vehicle, identifying herself as a nurse, asked if the woman needed any help.
The victim said she was fine and didn't need any help and the nurse then drove on.
Soon afterwards, an unknown man approached, walked with her for a while and assaulted her near to the Esso garage on Dorcan Way.
He is described as white with dark hair, and wore jeans, a dark jumper and black and white trainers.
Det Insp Paul Hacker said: "We would like to hear from anyone who was in this area of town during the late evening of Thursday, 10 September and who may have seen or heard anything suspicious.
"Perhaps you may have seen a woman walking alone or accompanied by a male around this time?
"We're also keen to hear from the nurse who stopped just before the assault to check that the young woman was alright - if that was you, please contact us.
"The area is surrounded by major roads; if you were driving around that part of Swindon perhaps you have dashcam footage which might also help us.
"If you have any information which could help our enquiries please contact us on 101, quoting crime reference number 54200091255."
Alternatively, people can report anonymously via Crimestoppers on 0800 555 111.