Firefighters battled for half an hour to extinguish a car on fire.
Weymouth Relief Road was blocked southbound at the A353 Jurassic Roundabout due to the fire this afternoon.
Police and firefighters were called to the scene.
A spokesman for Dorset and Wiltshire Fire and Rescue said: "We were called to the A354 at 2.18pm today.
"One crew from Weymouth attended, found the car well alight, and extinguished the blaze using two breathing apparatus wearers and one hose reel jet.
"This took about half an hour."
Travel was affected between Dorchester and Weymouth, and was moving very slowly.
The road has since reopened and traffic has returned to normal.
A Dorset Police spokesman said: "We were called with the fire service.
"Fire blocked off the road and there was a lot of smoke.
"The local authority has been called to due oil on the road, and there may also be damage to the carriageway.
"The vehicle was moved off the road at 2.45pm."
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