Emergency services were called to crashes across the county yesterday.
The A34 southbound was closed at the A4185 junction at Chilton near Didcot at around 9am following a collision.
Thames Valley Police and the air ambulance were both called to the accident.
There were delays of around 30 minutes with three miles of congestion at around 10.15am following the incident which was cleared by 10.30am.
Another crash involving a lorry then took place on the M40 northbound in the evening between junctions 10 and 11 between Banbury and Bicester.
The road was closed throughout the evening.
A statement from National Highways said: "The M40 in Oxfordshire has been closed both ways. Traffic officers are on scene, and all emergency services are en route.
"Early reports are suggesting that the closure will be in place throughout the evening."
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