A jogger was left injured after a hit-and-run collision with a car.
The woman suffered a broken ankle after the day-time incident.
Police are now appealing for witnesses to help them trace the driver of the mystery vehicle.
The incident happened just off Sniperley Roundabout, on the A167, near Durham City, at around 11.10am on Monday.
As the jogger, who is in her 30s, crossed Dryburn Park, police she was hit by what is believed to have been a silver Vauxhall Astra.
Collision investigator PC Nick Downing, who is leading the investigation, said: “We would like to hear from anyone who saw the collision or has any information which would help the investigation.
"In particular, we would ask anyone with a Dash Cam who was travelling in the vicinity at the relevant time to review the footage they have for any signs of the collision, the jogger or indeed a silver Vauxhall Astra-style vehicle.”
Anyone who witnessed the incident, or has relevant information is asked to contact PC Downing on 0191-3752159 or email@example.com, quoting the reference DHM-05112018-0163.