The M5 has been shut in both directions in Somerset after a crash involving two vehicles.
National Highways said traffic had been stopped between junction 25 at Taunton and junction 24 at Bridgwater.
Avon and Somerset Police said one person had been airlifted to hospital and other emergency services were at the scene.
Drivers have been advised to use alternative routes. However, roads through North Petherton into Bridgwater are reportedly already very busy.