Part of the A14 near Newmarket is shut due to a fire at a petrol station.
Emergency services were called to the blaze at the Rowley Mile garage at about 1.25pm on Sunday.
A spokesman for Cambridgeshire police said the eastbound carriageway is currently closed.
Pictures from the scene show at least one car engulfed in flames, while black smoke has been sent into the sky.
Drivers are advised to avoid the area until "further notice".
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