The A27 has been closed eastbound due to a crash close to the Southwick Tunnel.
Police say it is 'early days' but four or five vehicles are believed to be involved.
They were called shortly after 5pm and are still at the scene.
Drivers are advised to avoid travelling eastbound on the A27 as it is expected to be closed for some time.
If you saw the incident call the newsroom on 01273 544547.
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