The A14 westbound has re-opened between Elmswell and Rougham after a “serious crash” closed it for more than eight hours.
Police were called at 0.53am to the single-vehicle crash just before junction 45 at Rougham.
The police spokesman could not yet comment on injuries, but said more information would be available soon.
A volunteer doctor from the Suffolk Accident Rescue Service (SARS) emergency medical charity also attended the scene to support the East of England Ambulance Service.
A spokesman for SARS said they could provide no further information at this time.
The westbound carriageway was completely closed from junction 47 (Elmswell/Woolpit) to junction 45 (Rougham) while police carried out initial investigations and there were delays of at least 15 minutes.
A diversion was put in place.
For more traffic information see here or follow @HighwaysEAST on Twitter.
For urgent real-time help, Highways England's contact centre team can provide up-to-the-minute information on 0300 123 5000.
The police investigation is underway.
-More information to follow.
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