A road was closed late on Saturday night after a serious car crash involving five people.
Emergency services were called to Brooms Lane, Leadgate, near The Jolly Drovers pub at around 10.15pm.
It is understood the car rolled on to its roof and three people – a man and two women – became trapped.
County Durham Fire and Rescue Service said a man and a woman had managed to get themselves from the car before they arrived.
The fire services group manager Michael Pearson said: “We assisted in getting the other three out by working with the ambulance service.
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“It was quite a complex road traffic collision that took quite a bit of work from the crews, police, fire and ambulance. We worked together to help the casualties.
“Our thoughts are with the family and friends who have been involved in this collision.”
The road was closed by police last night while investigations were carried out.
Durham Constabulary and North East Ambulance Service has been contacted for further information.
A spokesperson for North East Ambulance Service said: "We were called at 10.07pm last night to reports of a car on its roof and some of the occupants trapped inside near Hanging Stone.
"We dispatched four paramedic crews, two clinical team leaders, a doctor and one hazardous area response team.
"Four patients were taken to the Royal Victoria Infirmary in Newcastle with serious injuries."
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