Dozens of flights are cancelled after a fire rips through a parking garage at London's Luton Airport

The burnt out shells of cars, buried amongst debris of a multi-storey car park are seen at Luton Airport in Luton, England, Wednesday Oct. 11, 2023. (Jacob King/PA via AP)

LONDON — Thousands of travellers faced disruption as all flights were suspended Wednesday at London's Luton airport after a fire tore through a newly built parking garage, destroying vehicles and partially collapsing the structure.

Four firefighters and an airport employee were treated for the effects of smoke inhalation after the fire, which broke out on Tuesday evening.

Officials at the airport, which is located about 56 kilometres (35 miles) north of central London, said emergency crews remained at the scene Wednesday as a precaution but travellers were starting to return to the terminal. It said flights were expected to resume departures at 3 p.m.

London Luton Airport is a hub for easyJet, Ryanair and other budget airlines running flights to destinations in the United Kingdom and Europe.

Investigators think the fire started with a diesel vehicle, according to Chief Fire Officer Andrew Hopkinson of the Bedfordshire Fire and Rescue Service. The recently opened parking garage did not appear to have sprinklers, he said.

"And then that fire has quickly and rapidly spread," Hopkinson told reporters. More than 100 firefighters were deployed to tackled the blaze, he said.

Authorities said they don't believe someone started the fire intentionally.

Some passengers had to sleep on the floor in the airport or wait at the nearby railway station because their flights were cancelled or delayed.

Nikodem Lesiak, a university student trying to return to Poland, said he spent the night at the station.

"When we got here, we found out Luton is burning and everything is closed, and we were supposed to have our flight at 7:50 today but it was cancelled," he said.

Video posted on social media and on the websites of British news outlets showed police and fire department vehicles gathered outside a multi-story parking structure where the top level was engulfed in flames.

Russell Taylor, 41, an account director from Kinross in Scotland, saw the flames after flying in to Luton from Edinburgh. He told the PA news agency that he first saw a couple of fire engines with a car on fire on an upper level of the garage, which served Terminal 2.

"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," he said. "The speed in which the fire took hold was incredible."

The garage partially collapsed.