Two road workers suffered serious injuries when a car hit them while they were closing a lane in Gloucestershire.
The car also hit two empty stationary vehicles when it crashed on the A417 near Cirencester, on Tuesday night.
The injured workers, one aged in his 20s and one in his 30s, were taken to Southmead Hospital in Bristol.
A 41-year-old man, from Portsmouth, was arrested on suspicion of dangerous driving and remains in police custody.
Gloucestershire Police were called to the southbound carriageway, between the Duntisbourne Abbots and Quarry junctions, at around 21:00 BST.
A number of workers were in the process of closing the lane when the men were hit by a grey Chevrolet Orlando.
One of the men, who is in a serious but stable condition, remains in hospital.
Police have appealed for witnesses, or anyone with dashcam footage, to come forward.
The road was closed after the crash, but has since been reopened.