A man has been airlifted to hospital with life-threatening injuries after being hit by a minibus on the A690 near Houghton-le-Spring .
Emergency services were called to the eastbound carriageway following reports of a collision at 8.24am on Tuesday.
At first just one lane was blocked but police put a full road closure in place at around by 9am to allow the Great North Air ambulance to land.
One man was airlifted to the Royal Victoria Infirmary after sustaining life-threatening injuries.
A North East Ambulance Service spokeswoman said: "We were called at 8.24am to reports of a road traffic collision on the A690 between a pedestrian and a minibus.
"A man has been transported by air to the RVI. His condition is currently not known."
The incident led to huge tailbacks on the A690 with diversions in place.
Police are now urging any witnesses to the incident to get in touch.
A Northumbria Police spokesman said: "Police received a report of a collision on the A690 Durham Road on Tuesday, August 20.
"At about 8.35am officers attended the scene where a man had collided with a vehicle.
"Ambulance service attended the scene where the pedestrian was taken to hospital. He is described as being in a life threatening condition.
"The road has now fully reopened and police are appealing for information.
"Anyone who may have witnessed the incident or has any dashcam footage is asked to contact police on 101, quoting 177 200819, or upload dashcam at Northumbria Police online."
The westbound carriageway reopened to traffic just after 10am once the air ambulance had departed.
Meanwhile, the eastbound carriageway reopened just after 11am after police conducted an investigation at the scene.
