Flights have been resumed after being grounded for over 12 hours due to an inferno that swept through Luton Airport car park.
London Luton Airport has reopened after a large fire tore through a multi-storey car park, causing it to partially collapse.
Hundreds of cars were damaged following the major blaze, which fire chiefs believe started from a diesel car just before 9pm on Tuesday.
Four firefighters and a member of airport staff were taken to hospital suffering from smoke inhalation and another firefighter was treated at the scene.
While the fire was put out by Wednesday morning, flights remained suspended until 3pm on Wednesday, with around 25,000 passengers suffering disruption as at least 140 flights were cancelled.
The disruption saw passengers sleeping on the floor of the terminal - ITV News Anglia reporter Callum Fairhurst described the scene on Wednesday and said: "It looks like a normal busy airport, but there are people on make-shift beds on the ground and a sea of orange and red on the departures board, indicating cancelled or delayed flights for across Europe."
Flights resumed on Wednesday afternoon with the arrival of a Wizz Air flight at 3.26pm.
The car park did not have a sprinkler system, early investigations by the fire service revealed.
Andrew Hopkinson, chief fire officer for Bedfordshire Fire and Rescue Service, said the fire was believed to have started with a diesel vehicle.
“We don’t believe it was an electric vehicle,” he said.
“It’s believed to be diesel-powered, at this stage all subject to verification. And then that fire has quickly and rapidly spread.”
Videos posted on social media show large flames coming from the top floor of the car park, as the fire service declared the blaze a major incident on Tuesday night.
An airport spokesperson described it as a "significant fire", adding that it had "resulted in a partial structural collapse" of the building.
More than 15 crews from Bedfordshire Fire Service tackled the blaze with nearby residents advised to close their windows to avoid the smoke.
A brigade spokesman said: "One half of the structure is fully involved in fire and the building has suffered a significant structural collapse.
"Fire crews are working to extinguish the fire and prevent it from spreading to adjacent buildings and vehicles on air side of the airport."
The service said shortly before 9am on Wednesday that the fire had been extinguished, but crews would be on the scene through the day.
It is believed hundreds of cars could have been damaged by the collapse.
Describing the car park, Luton Airport's website said: "Our brand new multi-story car park offering secure, on-site parking using just a five-minute walk to the terminal entrance."
Russell Taylor, 41, an account director from Kinross in Scotland, saw the flames after flying in to Luton Airport from Edinburgh.
He said: “There were a couple of fire engines with a car ablaze on the upper floor of the car park at just after 9pm.
“A few minutes later most of the upper floor was alight, car alarms were going off with loud explosions from cars going up in flames.
“The speed in which the fire took hold was incredible.”
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