Police have spoken to a driver who believes he hit a man on the A40 last night.
The victim in his 20s died in the accident, which happened near Witney.
Police said it was therefore not a hit and run and no one has been arrested.
Officers were called in the early hours to reports of a man lying in the road on the eastbound dual carriageway between Witney and Cogges.
They found a man with fatal injuries.
The man’s next of kin have been made aware and are being supported by specially trained officers.
Police are appealing for witnesses and for anyone who has dash-cam in their vehicle to check if it has captured anything that can assist the investigation.
They also want anyone who saw a man walking on the A40 at any stage overnight to contact them.
You can make a report online or by calling 101, quoting reference number 43220118000.
The A40 was closed overnight while this incident was investigated, but re-opened at 8am.
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