A military vehicle is on fire on the westbound carriageway and police have taken the precaution of closing the M4 between junctions 13 and 14 in both directions. Drivers are being urged to avoid the area completely until further notice.

The vehicle is thought to be carrying gas.

No one has been injured in this incident. Fire services and emergency crews are on the scene. The matrices (electronic signs) are diverting traffic but there are heavy delays already.