A38 in both directions is blocked, and there are long delays due to an accident near B3271 Liskeard Road. One of the vehicles involved has gone off the road.
Police say the road could be blocked for some time.
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This afternoon's rain will clear this evening, bringing a mild night and morning tomorrow.
Cloudier this afternoon, and mild temperatures tomorrow morning.
A retired solicitor from Bristol has died after being swept overboard while competing in the Clipper Round the World yacht race.