British police say they have arrested 15 demonstrators protesting plans for a new runway at London's Heathrow Airport.

A group of climate-change activists lay down across an access road to the airport early Saturday. Others gathered nearby holding signs reading "Heathrow expansion will destroy thousands of homes" and "Protect the planet, no more runways."

London's Metropolitan Police force says officers made 15 arrests "for obstructing the highway and public order offences."

Last month, the British government approved plans to build a third runway at Heathrow despite concerns about air pollution, noise and the destruction of hundreds of homes.

Protest group Rising Up! said the runway had been approved "despite mass opposition from local residents and the fact that doing so is incompatible with the U.K.'s own laws on climate change."