Abingdon Road has reopened after a pedestrian collided with a car.
The incident happened in Lake Street at about 1pm and a woman is believed to have been taken to hospital with serious injuries.
Thames Valley Police spokeswoman Connie Primmer said a blue Renault Clio was involved in the incident.
South Central Ambulance Service said it was called to Lake Street off Abingdon Road at about 1pm and medics were currently treating a woman.
The woman is believed to have suffered pelvic and leg injuries.
Oxford Bus Company diverted services via Donnington Bridge and Iffley Road.
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