The A385 in both directions is blocked with long delays and queuing traffic due to the accident near the Berry Pomeroy turn-off.
There is congestion to the A381 (Brutus Bridge roundabout) eastbound and to Fairparks Cattery westbound. Roads through Totnes are also very slow as traffic looks to divert.
The accident was reported to emergency services just before 4.30pm.
Devon Live has contacted Devon and Cornwall Police for more details about the accident and will post news of the incident as we get it in the blog below.