Airport Expansion: Protest Disrupts Flights

More than 20 flights were canceled on Monday at Heathrow Airport here in London after members of an environmental group cut through a perimeter fence and chained themselves to one another on a runway to protest against the possible expansion of the airport.

At a time of heightened vigilance in Britain, the security breach fanned concerns about security at Europe’s busiest airport after the activists gained access to the northern runway.

About a dozen protesters from the group Plane Stupid managed to cut through the wire fence and enter the runway at 3:30 a.m. to demonstrate against a politically divisive proposal over a third runway at Heathrow.

The police said six protesters had been arrested. Twenty-two flights were canceled as a result of the disruption, the airport said, although other flights on the northern runway continued to take off during the protest.