FRANKFURT, Germany — Airlines across Europe canceled flights bound for London's Heathrow Airport Thursday, and some airports said they could take on some of the diverted traffic.

Heathrow, Europe's busiest airport, was closed to most incoming European flights Thursday morning, after authorities announced they had uncovered a terrorist plot to blow up several aircraft flying between the U.S. and Britain using explosives smuggled in hand luggage.

Massive delays created after authorities began enforcing new security regulations banning hand luggage forced many European carriers to cancel their flights to Heathrow.

British Airways canceled all of its short-haul flights to and from Heathrow through Thursday afternoon. The airline advised passengers to avoid traveling if possible.

At Amsterdam's Schiphol airport, KLM spokesman Hugo Baas said the airline had canceled five flights to Heathrow.

"The backlog for people traveling to and through London is in the hours. That's going to create a ripple effect throughout the day, and increase as long as the airport remains closed," he said.

He said KLM was diverting to other London airports, and substituting larger planes where possible to increase the number of people getting through.

Cicero Alves Do Nascimento, a 47-year-old Brazilian martial arts teacher, was stuck at Schiphol after his British Midland flight to Heathrow was canceled.

"This is not fun at all. You get no compensation. Nobody gets any help here. You feel abandoned," he said, adding he was rebooked on a flight for Friday but got no voucher for a hotel or food because the airline said it wasn't to blame.

Frankfurt Airport, Europe's second-busiest, said it was prepared to take any traffic diverted from Heathrow. Spokesman Wolfgang Schwalm said security measures had been increased but that no ban on hand luggage had been enacted.

Other airports, including Amsterdam's Schiphol and Charles De Gaulle in Paris, also said they would be able to accommodate Heathrow-bound planes if necessary.

In Berlin, easyJet, British Airways, AirBerlin and Ryanair canceled their London-bound flights. All flights from Athens to airports in the London area were canceled, Athens International Airport said.

Air France canceled all Thursday morning flights to Heathrow because the airport was "saturated," an Air France spokeswoman said on condition of anonymity in accordance with the airline's policy.

Spain's Iberia said it had canceled four flights to Heathrow, and Italian carrier Alitalia stopped six flights through London.

SAS, the flag carrier for Sweden, Norway and Denmark, canceled its flights to Heathrow from Stockholm, Copenhagen and Oslo.