According to The Thames Valley Police, an investigation has been launched by police after a woman was found in a ‘distressed state’.
The crime happened between 1.15am and 1.30am on Sunday morning, the second of October.
An ambulance was flagged down in the area of the triple roundabouts of Buckingham Street, Bicester Road and Oxford Road.
The woman was taken to hospital, but has since been discharged.
Senior Investigating Officer Detective Inspector Simon Tyas, said: “This is a concerning incident, in which a woman has reported being raped in the early hours of Sunday morning.
“We are aware that members of the public were in the area and may be able to assist us with this investigation as they may have vital information which can help us.
“I would appeal to anybody who was in the vicinity of the triple roundabouts during this time period to please get in touch with Thames Valley Police by calling 101 or making a report online, quoting reference number 43220441378.”
CCTV footage is currently being reviewed.
Police said: “We are treating this as an isolated incident and there have not been any reports of a similar nature before or after this incident.
“However, there will be a continued presence of police in the area while our investigations continue, and the victim is being supported by specially trained officers.
“If you have any information that may assist the investigation, please get in touch with us.
“For 100% anonymity, you can also call the independent charity Crimestoppers on 0800 555 111.”