Police are appealing for witnesses to a collision that took place in Eastington at the beginning of this month.
Police were called to the A38 Hilltop Garage on Claypits Hill at around 8.30pm on Saturday 1 October with a report of a two vehicle collision.
The collision involved a red Citroen C3 and white BMW 420D coupe.
The driver of the Citroen sustained serious injuries and was taken to Gloucestershire Royal Hospital for treatment.
The driver of the BMW had left before police arrived and officers are asking them to come forward so that their details can be taken as well as give an account of what happened.
Officers are also asking anyone who saw the BMW in the lead up to the collision to make contact or anyone who has dashcam footage they feel may be relevant.
Information can be provided online by completing the following form and quoting incident 438 of 1 October: www.gloucestershire.police.uk/tua/tell-us-about/cor/tell-us-about-existing-case-report/
You can also call police on 101 and quote the same incident number.