A man has been airlifted to hospital with serious injuries following a collision between a car and a motorcycle on the A145 at Brampton.
The incident happened shortly before 1.30pm on Wednesday, Suffolk police said.
Officers remain at the scene and have closed London Road between Station Road and The Street.
The motorcyclist, a man, was treated at the scene by volunteers from the Suffolk Accident Rescue Service (SARS) before being taken to Addenbrooke's Hospital in Cambridge by air ambulance.
A Suffolk police spokesman said the man suffered potentially life-threatening injuries.
The driver of the car was treated for minor injuries.
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