An air ambulance has been called to the scene of a crash involving a motorbike and car.
Police were called to the collision on the B1146 Dereham Road just after 12.30pm on Wednesday, April 13.
The road was closed at 12.50pm and emergency services remained at the scene.
A police spokeswoman said: "We were called to a collision involving a motorbike and a car on Dereham Road in Colkirk.
"It is thought those involved have sustained serious or life-threatening injuries.
"Drivers are advised to avoid the area."
The road remains closed as of 3pm.
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