Thousands of passengers using budget airlines to and from London's Stansted airport suffered severe disruption Monday following an environmental protest which temporarily shut down the airport's single runway, dpa reported.
Irish carrier Ryanair, the airline most affected by the nine-hour protest by environmental group Plane Stupid, said it cancelled 56 flights to short-haul destinations in Europe, including Poland, Germany, France and Italy.
Other airlines decided against cancellations, the airport said.
Police said 57 protestors were arrested after cutting through the fence with bolt-cutters and chaining themselves together on the runway, using sheets of security fencing for protection.
The protest hit the first wave of Monday morning flights in an out of Stansted, which is London's third-biggest airport, situated some 50 kilometres north-east of the capital.
Plane Stupid said the protest was to highlight the "hypocrisy" between government climate change goals and reality, following the green light for the construction of a second runway at Stansted.
"We're here because our parents' generation has failed us and its now down to young people to stop climate change by whatever peaceful means we have left," a statement posted on the group's website said.
Their protest would prevent the release of thousands of tonnes of greenhouse gas emissions into the atmosphere, Plane Stupid said.
However, the protest was condemned by the government. A spokesman for Prime Minister Gordon Brown said: "Of course everybody has has a right to protest, but people also have a right to travel without unnecessary hindrance."
Ryanair called for an investigation into what it described as an "unacceptable disruption" of thousands of passengers.
An airport spokesman said that while lessons would be learnt from Monday's protests, operators were not prepared to run the airport like a "fortress."