A man has been arrested on suspicion of drug-driving after a woman was injured when a car hit a wall in Somerset.
The crash happened on the A39 near Glastonbury at about 02:50 BST, Avon and Somerset Police police said.
The woman was taken to hospital with potentially life-changing injuries. The arrested man, who is in his 30s, is also suspected of causing injury by dangerous driving.
The A39 has been closed at Northload Bridge roundabout.
Police said it would remain closed on Wednesday while officers conclude investigations at the scene.