The A11 is closed northbound on the Suffolk-Norfolk border near Thetford because of a serious crash involving 2 vehicles.
The road is closed between the B1106 at Elveden and the B1107 at Thetford.
Highways England have put in a diversion turning off the A11 at Elvedon onto the B1106. Then it's a right turn onto Green Road before joining the B1107 and heading towards Thetford to re-join the A11 northbound.
Drivers are advised to allow extra time for their journeys and consider an alternative route.