A video shows an air ambulance circling above the scene of a major crash on the A34 near Didcot. 

The A34 southbound between Didcot and Chilton has been closed since around 1pm after a major crash. 

READ MORE: Photos show police and ambulance after major crash on the A34

Drivers have been stuck in traffic for more than four hours with one taking a video of an air ambulance circling overhead. 

In a statement issued this evening, a spokesman for the air ambulance said: "Following treatment on scene, a patient was taken to hospital by road ambulance, with the air ambulance crew travelling with the patient to continue their care."

The major crash appears to have involved a flat-bed lorry which one driver described as facing the wrong way.