A 23-yar-old man was killed and three others injured when a car they were travelling in crashed on the A40.
Police and paramedics were called after a silver Renault Clio hit the central reservation barrier between the Forest Hill and Wheatley junctions at 4.20am yesterday.
When emergency services arrived, the car was on its roof and two people were found in the carriageway.
The 23-year-old was taken to Oxford’s John Radcliffe Hospital, but later died.
Police spokesman Victoria Brandon said a second man was last night in hospital in a serious condition while two others were described as walking wounded.
The A40 was closed between the Headington roundabout and the B4027 for Wheatley until 7.30am while police investigated.
PC Murray McLean said: “I appeal to anyone who witnessed the collision to contact police immediately.”
Officers did not know last night whether the dead man was the driver or a passenger, Mrs Brandon added.
All four involved are believed to be from Buckinghamshire and east Berkshire.
No other vehicles were involved in the crash and no-one has been arrested.
A spokesman for South Central Ambulance Service said two patients had been thrown from the car and all four were taken to the John Radcliffe Hospital.
No one from the hospital was available to comment.
Anyone with information should contact PC McLean on 08458 505505 or Crimestoppers on 0800 555111.
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