A man aged in his fifties suffered serious injuries believed to be as a result of an assault in Ingleby Barwick.
The incident, on Friday 19th January, is reported to have happened between 7am and 8am on Pothos Road on the new Beckside Manor estate, when a male on a motorbike with no reg plate assaulted the man by punching him, causing serious facial and abdominal injuries.
The man is currently receiving treatment at James Cook University Hospital.
Officers are appealing to anyone who may have witnessed the incident or anyone who may have CCTV or dash cam footage to get in touch.
Anyone with information is asked to contact Stockton CID on 101, or Crimestoppers anonymously online at www.crimestoppers-uk.org or by calling 0800 555 111.