A woman in her 70s has been left with life-threatening injuries after being struck by a van on the A350 at Lacock.
Emergency services were called to the collision at around 8.45am on Thursday, 1 October, involving the pedestrian and a van.
The woman suffered life-threatening injuries and was taken to hospital for treatment.
Wiltshire Police confirmed that the 39-year-old driver of the van has been arrested on suspicion of drug driving and causing serious injury by careless driving.
He has been taken into police custody for questioning.
A350 closed for collision investigation
The A350 remains closed while officers investigate the circumstances surrounding the collision.
The Serious Collision Investigation Team is appealing for witnesses and wants to hear from motorists who may have relevant dashcam footage.
Anyone who witnessed the collision or has footage which could assist investigators is asked to contact the team on 01225 694597, quoting log number 88 of 1 October.
Information can also be provided directly to the Serious Collision Investigation Team by email.
Police enquiries into the collision remain ongoing.
