Just Stop Oil supporters who blocked departure gates at Gatwick Airport have been arrested and are being removed, the airport has said.

Seven people entered the South Terminal at around 8am and “used suitcases with lock-on devices to block the departure gates”, Just Stop Oil claimed.

A video shared by the group showed the protesters sitting on the floor inside the airport, blocking an entrance.

Passengers with suitcases appeared to step over the activists and continue with their journeys.

Sussex Police said eight people had been arrested over the incident.

A spokesperson added: “Police responded to a report that protesters were demonstrating near the security entrance at the South Terminal in Gatwick Airport at around 8am today.

“Eight people have been arrested on suspicion of interfering with public infrastructure, and a heightened police presence should be expected at this time.

“The airport is functioning as usual, and no disruption has been caused by protest activity.”

A London Gatwick spokesman said: “London Gatwick is open and operating normally today.

“There are a small number of protesters at the airport who have now been arrested and are being removed from the airport.”

Prime Minister Sir Keir Starmer’s official spokesman said: “We recognise the democratic right of people to peacefully express their views, but obviously they should do so within the bounds of the law.

“And clearly being seen to significantly disrupt people’s summer holidays is no way of winning people around to your cause.”

In central London, environmental protesters have caused criminal damage and blocked access to the office building of the think tank Policy Exchange on Old Queen Street in Westminster.

One person has been arrested for criminal damage and the incident is ongoing, the Met said.

The members of Extinction Rebellion held banners bearing the words “Policy Exchange – cut the ties to fossil fuels”.

Leaflets given out at the demonstration listed the group’s demands, including “full and open disclosure” of where funding for the think tank comes from, increased transparency of Policy Exchange meetings with MPs and government departments, and the removal of charitable status for “any lobby group” that receives money from “big oil and gas”.

The group poured pools of black liquid outside the Policy Exchange building alongside a yellow sign reading “Caution: slippery with the truth”.

Last week, 10 Just Stop Oil activists suspected of planning to disrupt Heathrow Airport were arrested.

None of the activists were able to get into the airport, the Met said.

The latest action is part of the “Oil Kills international uprising”, the group said, taking place at airports around the world.

Mel Carrington, 63, a mother and former environmental consultant from Dorset, and Greg Sculthorpe, a mathematician from Doncaster, were said to be among the activists involved at Gatwick.

Earlier this month, the airport became the latest major airport to secure a High Court injunction in an attempt to stop would-be environmental activists trespassing on its land after receiving police intelligence over protest plans.

Timothy Morshead KC, representing Gatwick at the hearing, said such action could cause “severe disruption and financial loss” and “significant delays for passengers”.

Sussex Police has been contacted for comment.