Photos: Huge fire on double decker bus causes chaos in Dorset
The Morebus vehicle burst into flames on the A338 northbound out of Bournemouth at 1.20pm, and five passengers were led to safety by the driver.
The blaze was so intense that staff at Bournemouth Airport were warned of potential disruption to flights from the smoke.
Motorists faced huge queues, although one of the carriageways opened around an hour later.
The bus was completely burnt out by the fire but, luckily, no injuries were reported.
Fire investigators believe it could have been caused by an electrical fault.
Allen Westerby, watch manager at Christchurch Fire Station, told the Bournemouth Echo:"We were called to a double-decker bus on fire on the northbound carriageway of the A338.
"It's very badly damaged. There were five passengers on board, plus the driver. They were fine.
"The fire cause is being looked into and it could be an electrical fault, but the bus has been badly damaged and it needs to be recovered before an investigation can be done at the depot."
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