Police were called to a very serious crash on the M40 over the Oxfordshire border last night and closed the motorway.
The busy motorway was shut by emergency services at around 9pm to deal with the smash southbound between J4 and J3 in Buckinghamshire.
Highways England said traffic caught up within the closure was turned around from the rear of the queue while emergency services did investigation work at the scene.
An image from the traffic cameras along the motorway shows vehicles driving up the wrong side of the road to exit the motorway at a slip road.
The road was reopened some 7 hours after the crash, according to the National Highways.
Thames Valley police has been contacted for more details.
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