Police in Kent are warning motorists of congestion around the coast-bound carriage at junction 10 of the M20 following a four lorry crash.
Traffic is being diverted off the slip road at junction 10 and back onto the motorway via the on-slip at the same junction.
Delays in the area could continue until around midnight or the early hours of Friday as the damaged carriageway needs resurfacing.
Two lorry drivers were taken to hospital after the incident with serious injuries.
They remain in hospital at present. The other two lorry drivers were uninjured.
Inspector Geoff Wood, of Kent Police's Traffic Department said: "We are working to establish exactly what happened to cause this collision. Anyone who saw the collision or has any information should contact officers at Kent Police on 01622 798538."
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