SAO PAULO, Brazil (AP) — More than 25,000 passengers of a single airline in Brazil saw flights delayed or cancelled after a damaged cargo jet blocked the lone runway at one of the country's busiest airports for two days, officials said yesterday.

Separately, the check-in system at Tam airlines, Brazil's biggest, was down for three hours early yesterday at all locations around the world where the company operates, adding to the air transport chaos in Latin America's biggest nation. Critics say improving the nation's woeful airports is one of its biggest challenges before it hosts the 2014 World Cup.

Azul Airlines, which operates about 85 per cent of the flights at the Campinas airport north of Sao Paulo, said late yesterday afternoon that its flights would resume normal operations by early evening after the damaged cargo jet was removed from the airport's only runway. The jet, owned by US-based Centurion Cargo, blew out a tire upon landing Saturday night -- it took Brazilian officials until yesterday to locate the proper heavy equipment to remove the plane.

The Campinas airport, also known as Viracopos, was Brazil's ninth-busiest last year, according to government statistics, and was earlier this year named as one of three the government said it would privatise.

"Although operations at Viracopos have been freed up, delays and cancellations may still occur," Azul said in a statement.

A spokeswoman for Tam airlines declined to say how many flights were delayed or cancelled because of the problems with its check-in system. The company operates about 800 flights a day around the globe. With the check-in system down, passengers' tickets had to be processed by hand at airports. Brazilian TV showed long lines and crowded terminals at main airports in Sao Paulo and Rio de Janeiro.

Improving airports plagued with bottlenecks, long lines and poor infrastructure was a key promise made by the government in its winning bid to host soccer's premiere event in 2014. Hundreds of thousands of fans will fly between the 12 host cities for matches.

Brazil's airports have buckled under demand that tripled in the past decade. In 2002, airlines flew 34.3 million passengers on flights originating in Brazil. That rose to 107.8 million last year, Brazil's civil aviation agency reported.