Roads in Knowstone, South Molton will remain closed for a while, following a serious collision between a lorry and a motorcycle.
Emergency services, including an air ambulance and fire crews, are at the scene near the Moortown Barton picnic area, parallel to the A361.
Both vehicles caught fire, leaving a motorcyclist seriously injured.
There are closures between Beaples Moor Cross and Marley Moor and at Moortown Cross.
Drivers are asked to avoid the area. Diversions are also in place.
Anyone who witnessed the collision is asked to contact the police by email on firstname.lastname@example.org or phone on 101, quoting log number 93 of 12/09/17.