The A1081 has been closed after a coach caught fire on the bridge over Park Street.
Dozens of holidaygoers were spotted walking with their suitcases after the road was closed.
An eyewitness said: “This white coach caught fire. The plumes of smoke rising out of it were unbelievable.
“So many people were walking with their suitcases. The whole road’s closed and I hope people don’t miss their flights!”
A Beds Fire and Rescue spokesman said: “At 10.33am today we were called to a coach on fire on the A1088, Airport Way, on a bridge over Park St. Fire crews from Luton arrived nine minutes later and found the coach 100% involved in fire.
“There was only the driver on the coach at the time and he had been alerted to a fire in the engine at the rear of his coach by another driver. He had pulled up on the bridge as the fire took hold of the coach from the rear, working its way along the coach until it was all engulfed in flames.
“The fire was out by 11.15am. During the incident the emergency services directed those on their way to the airport to the Luton Parkway station so they could continue their journey to the airport unhindered.
“The driver suffered from smoke inhalation and was passed into the care of the ambulance service. The fire started accidentally in the engine of the coach.”
A Bedfordshire Police spokesman said the force was called at 10.35am to divert traffic.
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