Traffic heading east along the A31 near Wimborne is queuing near Candys Lane due to a collision which is partially blocking the road, reports the AA Traffic News website.
Two ambulances and two police cars are on the scene with the road partially blocked.
At least two cars were involved in the crash.
The seriousness of any injuries is not yet known.
Motorists are advised that journeys may take longer than expected.
Dorset Police and the ambulance service have been contacted for more information.