A 17-year-old boy has been arrested after an alleged rape of a teenager on common land in York.
Police are appealing for an "important witness" who stopped to ask if the victim of the offence was OK in the moments before it took place on Thurday, June 7.
The incident happened on Hob Moor, an area of common land on the outskirts of York.
Officers said that immediately before to the offence, the victim was in the alleyway that runs from Hob Moor Drive, on to Hob Moor itself.
She was upset, and was pushed against a garden fence. During this altercation, a man, possibly a runner, stopped and spoke to the victim to ask if she was OK.
Officers are appealing for the man to come forward, as he may have information which could help the investigation. They also want to hear from any other witnesses.
A 17-year-old boy, who is known to the victim, has been arrested and released on conditional bail.
Anyone with information is asked to contact North Yorkshire Police on 101, select option two and ask for York Serious Crime Team. Quote reference number 12180101227 when passing on information.