Officers are appealing for information after a car collided into a hedge before entering a ditch.
The incident happened off Blake Hall Road, Ongar, at around 2.50am on Friday, November 8.
Essex Police received a call that a man in a grey Fiat 500 was taken to hospital with serious injuries.
The collision followed a fail to stop incident just 30 minutes before where the suspect vehicle escaped.
A man has since been arrested on suspicion of theft of a vehicle.
Police have made a mandatory referral about the collision to the Independent Office for Police Conduct.
Anyone with information is asked to call our Serious Collision Investigations Unit on 101 quoting incident 88 of 08/11 or Crimestoppers anonymously on 0800 555 111.
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