The A27 is partially blocked due to a crash involving three vehicles.
The crash happened this morning just before 8am on the A27 eastbound near Hollingbury, Brighton.
Queues are stretching back A23 and roundabout at London Road.
It is unclear if there are any serious injuries at the scene.
A Sussex Police spokeswoman said: "Police were called to reports of a three-vehicle collision on the eastbound A27 at Hollingbury shortly before 8am on Monday, February 6.
"A lane closure is currently in place to allow emergency services to respond to the collision. No further information is available at this time."
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