A motorist who pulled over after a crash is being urged to come forward by crash investigators.
The appeal by Durham Constabulary comes after the driver and their passenger were seriously injured in a collision with another car.
The incident happened on the A689 west bound carriageway, Wynyard, at about 1pm on Friday, October 13.
The collision involved a silver Mercedes 4x4 and a white 3 series BMW.
Durham Constabulary would like to speak to anybody who may have witnessed the collision or saw the vehicles prior to the collision.
They would also like to speak to the driver of a black Jaguar who stopped and assisted at the time of the collision.
Sergeant Simon Kestle, from Durham Constabulary, said: “If anyone was driving westbound around the time of the collision who possesses a dashcam, recording the road conditions and weather please get in touch, this could prove significant to our investigation”.
Anybody with information is asked to call 101 quoting incident number 247 of October 13.