The East Anglian Air Ambulance was called to Kings Lynn this morning after a woman was hit by a vehicle.
The ambulance service received the call to Norfolk Street at 10.10am.
A rapid response car, an ambulance officer and a crew were dispatched to the accident and were backed-up by the air ambulance team.
The rapid responder treated the woman who had become unconscious after being hit.
The woman, who is believed to be in her 80s, was air lifted to Addenbrookes Hospital in Cambridge in a critical condition after sustaining substantial injuries.
The incident caused major disruption to traffic and there were reports of long queues with cars being unable to get through Gaywood Road.
Lynx Bus warned customers on twitter to expect 'major disruption to all services in and out of Kings Lynn'.
Police are appealing for witnesses following the accident. Call 101 with information.
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