Alicante airport remains closed after a fire caused the terminal to be evacuated.
Thousands of passengers are disrupted as flight cancellations stretch into a second day.
The Costa Blanca airport was evacuated on Wednesday afternoon when a fire broke out on the roof of the terminal.
Airport operator Aena tweeted: “For security reasons the airport terminal is being evacuated away from Alicante-Elche due to a fire on the deck.”
Aena said this morning that the hub would remain shut until 2pm local time (1pm GMT) while recovery from the blaze continued.
It urged passengers not to travel to the airport, and said they should contact their airline for more information.
Dozens of departures have been cancelled since the last flight, Ryanair to Dublin, took off at 4.05pm on Wednesday.
On Wednesday evening, Ryanair cancelled flights to East Midlands, Gatwick and Leeds Bradford, while easyJet grounded Gatwick and Liverpool departures.
On Thursday, Ryanair has cancelled a dozen flights between UK airports and Alicante, with round-trips from Edinburgh, Gatwick, Liverpool, Manchester, Newcastle and Stansted grounded.
An estimated 2,000 passengers are affected on these flights alone.
From Southend, easyJet has cancelled its morning departure.
Vueling has also cancelled a round-trip from Cardiff, while Jet2 has redirected its Birmingham flight to Murcia.
On Wednesday, most flights were diverted to nearby Murcia and Valencia airports.
The cause of the fire is not yet known.
Footage from eyewitnesses shared on social media shows plumes of smoke billowing from the terminal roof and passengers waiting around outside after being evacuated.
The Costa Blanca airport is the fifth-busiest in Spain. Last year, 15 million passengers passed through the airport – with many of them from the UK.
The city and wider Costa Blanca region is a popular holiday spot for Britons.
