The A27 westbound is currently closed because of a three-vehicle crash in Hove.
Police and firefighters are at the scene.
A Sussex Police spokeswoman said: "Emergency services are currently dealing with a three-vehicle collision on the A27 westbound at Hove.
"The collision which happened at 2pm today is close to the A293 westbound junction. The A27 westbound with that junction is likely to be closed for sometime."
Three people have been injured.
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