Firefighters have freed someone from a car on the A12, with traffic queueing for miles on both carriageways.
Suffolk Fire and Rescue Service was called to the scene of the crash, involving two vehicles, at 2.59pm, with three of their engines deployed to the scene.
A spokesman for the fire service said one person was trapped in their vehicle close to Stratford St Andrew.
According to AA route planner, the road is blocked and traffic is queueing due to a collision between two cars on the A12 Southbound, from Mill Lane to Buttons Road.
Traffic is affected between Farnham and Lower Hacheston. Queues are also building on Low Road.
The East of England Ambulance Service has been approached for comment.
Suffolk Constabulary is aware of the incident and officers are currently at the scene of the crash.
By 3.30pm, police confirmed that firefighters had cut one person from the car they were trapped in and they were in the care of paramedics.
The southbound carriageway is now open.
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