Police are appealing for witnesses after a 20-year-old man died in the first of a series of collisions on the A34 this morning.

A black Vauxhall Corsa overturned and rolled about 50m at about 2.33am on the southbound carriageway near Drayton.

A 20-year-old man was killed and three other passengers - two women and a man - were taken to Oxford's John Radcliffe Hospital with minor injuries.

Shortly afterwards a lorry and a breakdown truck transporting a blue Hyundai collided on the same carriageway.

Police said it was not yet clear whether the collision was as a result of tailbacks from the original crash.

The 46-year-old lorry driver received head injuries and was taken to the John Radcliffe with serious but not life threatening injuries.

The breakdown truck driver and his passenger, the driver of the Hyundai, were treated for minor injuries at the hospital and later released.

At about 3.40am, hydrochloric acid started to leaked from another lorry in the tailback onto the carriageway.

Police said this vehicle was not involved in any collision and added the spillage was dealt with by Oxfordshire Fire and Rescue.

The southbound carriageway was closed between the Marcham Interchange and Didcot until 10.20am this morning.

Sgt Kerry Clarke, of Abingdon Roads Policing, said: "This was a complex operation that led to the A34 being closed in one direction for nearly eight hours.

"A young man has been left dead and a number of others injured so we need to speak to anyone who saw either incident to contact us and help with our investigations."

Call police on 08458 505505 or Crimestoppers anonymously on 0800 555111.