A man has been arrested in connection with a Thames Valley Police investigation into a sexual assault which happened in Oxford at 12:45am yesterday.
The woman was walking along Bartlemass Road, when she was approached by a man, who said he would walk her home.
The victim wanted the man to leave her alone so she sat down by a parked car. He then sat down by her and sexually assaulted her under her clothing.
A member of public intervened and helped the victim. The man then fled the scene.
Police have since arrested a 29-year-old man on suspicion of sexual assault and he remains in police custody.
Thames Valley Police are continuing to investigate the incident.
Senior Investigating officer, Detective Inspector James Mather, said: "This was a traumatic incident for the victim and she is being supported by specially trained officers".
"If you have CCTV or may have been travelling along Bartlemass or Cowley Road between 12.30am and 12.50am this morning (11/11) and may have captured anything that could help our investigation then please do get in touch"
Anyone with information should call 101 quoting reference 43210509575 or make a report online using the same reference.