Luton Airport has been closed after a fire ripped through a multi-storey car park, causing it to collapse.
Firefighters are tackling the blaze which began on Tuesday evening and appears to have destroyed hundreds of cars.
Flights have been cancelled since the fire broke out at around 9pm and are expected to resume at around noon on Wednesday, the airport said.
The cancellations are affecting a number of Ryanair flights serving Dublin. The 8.20am and 7.15pm flights from Dublin to Luton have been cancelled, as have the flights to Dublin at 7.55am and 6.50pm.
The flights between Dublin and Luton at 4.15pm and 7.50pm are still scheduled as planned.
Four firefighters and a member of airport staff were taken to hospital suffering from smoke inhalation and another firefighter was treated at the scene.
Footage posted on social media showed flames and smoke tearing through cars parked at the newly-built airport car park.
Russell Taylor, 41, an account director from Kinross in Scotland, saw the flames after flying in to Luton Airport from Edinburgh.
He told the PA news agency: “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.
In a statement at 3am on Wednesday, the airport said: “Emergency services continue to respond to a significant fire in Terminal Car Park 2, which has resulted in a partial structural collapse.
“All flights are suspended until 12pm on Wednesday. Passengers are advised not to travel to the airport at this time.”
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.”
Describing the car park, Luton Airport’s website said the brand new multi-story car park is a five-minute walk to the terminal entrance. - additional reporting PA