A crash has closed the A31 between the B3073 at Canford Bottom and the A349 at Oakley at Wimborne on Saturday afternoon.
Surrounding routes are busy as a result as a local diversion is in place.
The route is expected to be closed till around 5pm for clean-up of a vehicle fire.
Public transport is also disrupted in the area.
In a separate incident, a male motorcyclist was airlifted to Southampton General Hospital following a crash involving a deer near Canford Bottom.