UK low-cost airline and holiday company Monarch Airlines has collapsed and been placed in administration, leaving 110,000 customers stranded abroad.
The UK's Civil Aviation Authority said it has been asked by the British government to charter more than 30 aircraft to bring the passengers back to the UK after the airline failed to renew a crucial licence.
Some 750,000 future bookings have been cancelled as a result of the company's failure, the largest to hit a UK airline, and customers have been told to keep away from airports as there will be no more flights.
Its demise has added to turbulence in the European airline industry after Air Berlin and Alitalia filed for insolvency this year.
Ryanair has also been forced to cancel thousands of flights because of problems finding enough pilots to fly them.
Shares of Monarch's rivals, easyJet, Ryanair and Wizz Air rose today on the prospect of reduced competition and the chance to acquire some of its assets.
Monarch, based at Luton Airport, north of London, and in business since 1968, has apologised to customers and staff.
"I am so sorry that thousands now face a cancelled holiday or trip, possible delays getting home and huge inconvenience as a result of our failure," Monarch Chief Executive Andrew Swaffield told employees in a message. "I am truly sorry that it has ended like this."
Customers affected by the company's collapse have been urged to check a dedicated website monarch.caa.co.uk for advice and information on flights back to the UK.
CAA chief executive Andrew Haines said: "We know that Monarch's decision to stop trading will be very distressing for all of its customers and employees.
"This is the biggest UK airline ever to cease trading, so the government has asked the CAA to support Monarch customers currently abroad to get back to the UK at the end of their holiday at no extra cost to them.
"We are putting together, at very short notice and for a period of two weeks, what is effectively one of the UK's largest airlines to manage this task.
"The scale and challenge of this operation means that some disruption is inevitable. We ask customers to bear with us as we work around the clock to bring everyone home."
The CAA said all Monarch customers who are abroad and due to return to the UK in the next two weeks will be flown home.
The flights will be at no extra cost to passengers and they do not need to cut short their stay, the regulator said.
Here, the Commission for Aviation Regulation, the national enforcement body in relation air passenger rights on flights from Irish airports, said: "So far as the Commission is aware, Monarch Airlines had no flights scheduled to depart from Irish airports and thus the Commission has no role to play in relation to the cancellation of Monarch flights."