A 36-year-old man has been arrested on suspicion of causing serious injury by dangerous driving following a two-car crash near Chilton on Friday night.
The incident happened on the A167 at Rushyford roundabout shortly after 6.30pm and involved a Seat Leon and Mercedes Sprinter.
During the incident, a passenger in the Mercedes suffered serious injuries and was taken to James Cook University Hospital in Middlesbrough for treatment.
One driver was arrested on suspicion of causing serious injury by dangerous driving and failure to provide a specimen.
He has since been released under investigation.
Police are now keen to speak to anyone who may have dashcam footage of the incident.
Anyone with information should call PC Jamie Pitt on 101 quoting incident number 357 of October 11.
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