Gloucestershire Police are appealing for witnesses after a motorcyclist was involved in a collision with a tractor.
The incident occurred shortly after 9pm on Saturday 11 April, on the A4135 near Owlpen, Gloucestershire, close to the B4058 Horsley Junction.
The collision involved a red Ducati 916 motorcycle and a John Deere tractor towing a trailer.
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The motorcyclist, a 52-year-old-man from Dursley, sustained serious arm and leg injuries.
He was treated at the scene by paramedics, before being taken to Southmead Hospital in Bristol, where he is currently described as being in a serious but stable condition.
The tractor driver, a 25-year-old man from Tetbury, was uninjured.
The road remained closed for four hours, while officers conducted a detailed examination of the scene.
The investigation team are particularly interested to hear from two potential witnesses.
The driver of a dark coloured Audi Estate that was travelling from the Calcot Crossroads direction, towards Wotton Under Edge and was overtaken by two motorcyclists shortly before the collision.
The driver of a small hatchback, who was waiting at the B4058 junction to join the A4135 and turn right towards Wotton Under Edge.
Anyone with information is asked to contact Gloucestershire Police on 101 quoting Incident No 403 of 11 April.