The air ambulance was called out after a car overturned on the A149 at Antingham.
Police were called to reports of a crash involving one vehicle at 3.10pm on Wednesday, June 13.
The car had overturned and injuries are thought to be serious.
The fire and ambulance service also attended the incident.
A spokesperson for the East Anglian air ambulance confirmed they had been at the scene of the crash.
Two fire crews from North Walsham and Cromer released two casualties from the car.
In a tweet at 3.39pm Norfolk Police said: 'A149 Antingham closed due to RTC #norfolkroads.'
The road reopened at 6.30pm.
Did you witness the crash? Email: jessica.frank-keyes@archant.co.uk
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