There was traffic chaos at Heathrow Airport this morning after climate change protestors blocked a tunnel to demonstrate against the building of a third runway at the site.
Demonstrators, apparently from the Plane Stupid campaign group, blockaded the airport's inbound tunnel, preventing people from accessing Terminals One, Two and Three.
People tweeted pictures and video showing the extent of the traffic, which was reportedly backed up to the M4.
Plane Stupid tweeted pictures of the demonstration, alongside environmental arguments against another runway.
The Metropolitan Police confirmed it had made five arrests.
It said it was called at 7.42am to deal with "a protest near the inbound tunnel of Heathrow airport".
At of 10am, the airport said it was still clearing the tunnel and advised passengers to allow extra time to get to the airport.