Highway bosses have said they are unsure when the M40 will reopen following the death of a man in a crash.

Two lorries and a van collided on the southbound carriageway at Junction 10 at 5.43am today, with both north and southbound carriageways currently shut.

One of the lorries was carrying oxyacetylene cylinders, which are potentially explosive, and firefighters are assessing the situation.

Police said the canisters may have become unstable and will need to cool down before they can be safely moved.

The road is closed in both directions between Bicester and Banbury, and police have advised motorists to take alternative routes.

An agency spokesman said: “We can only guess when the road will be back open again.

“We are not in any position to say with any great certainty.”

A spokesman for the South Central Ambulance service said no-one else had needed treatment.

Sarah Dobbie, duty manager of the Cherwell Valley Services, near Ardley, said the petrol station had been closed by police.

She said: “They shut us because everyone was coming into us thinking they could get back on to the motorway.

“Of course they couldn’t and it just got gridlocked. It was chaos.”

Tail backs on the south bound carriageway are back to Junction 12 at Gaydon, and traffic is reportedly very busy on the A34, between Islip and the M40, and the A422 going into Banbury.

The Highways Agency diversion advice is: Drivers coming south should come off at Junction 11 on the M40, continue on to the A422 to Brackley then take the A43 southbound, on to the B430 and follow to Western on the Green, join the A34 and then rejoin the M40 at Junction 9.

Northbound traffic should come off Junction Nine on the M40, join the A34 southbound and then take the B430 at Weston-on-the-Green, take the A43 to Brackley and continue to the A422 to Banbury and then rejoin the M40 at Junction 11.