A man in his 60s was cut out of a car after being trapped following a crash between two vehicles.
The accident, involving a Nissan and Toyota Hilux, happened on Weasenham Road just after 3pm today.
Fire crews from Massingham and King's Lynn freed the man, and two ambulance crews, two ambulance officers and the East Anglian Air Ambulance were sent to the scene.
A spokesman for the ambulance service said the man was taken to the Queen Elizabeth Hospital in King's Lynn by land ambulance in a critical condition.
A second patient was also taken there, with minor injuries.
Police said the road re-opened at 8.37pm.
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