The A1 was closed by police between the B6471 in Huntington and the A6093 in Haddington.
After a serious accident in East Lothian, a two-lane road was blocked in both directions.
The A1 motorway closed at 4:45 pm between the B6471 in Huntington and the A6093 in Haddington.
The police confirmed that the cordon was due to a serious car accident and officials are still at the scene.
Traffic Scotland said drivers should expect delays after the crash.
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