Activists block Heathrow Airport tunnel

Demonstrators blocked an entrance tunnel to London's Heathrow Airport on Thursday in apparent protest at plans to build a third runway at the global hub.

London's Metropolitan Police said that they arrested five people at the tunnel, which links roads around Heathrow to the airport's terminals.

A Twitter user named Ian Stopher posted video footage of the protesters blocking the area with a vehicle with a banner that reads "No new runways."

Plans by Europe's largest airport to expand its capacity to meet growing demand by adding a third runway have been met by fierce opposition by residents, environmentalists and some British politicians including London Mayor Boris Johnson, who has campaigned to build a new airport in the Thames Estuary instead.

The aviation industry broadly maintains that expanding Heathrow is the best way to create new jobs and boost Britain's economy.