The two men were held in the early hours “on suspicion of conspiracy to commit a public nuisance in relation to operations at Heathrow,” the Metropolitan Police said in a statement. Another seven people were detained Thursday in response to plans to fly drones near the airport, the force said.

The Heathrow Pause group said on Twitter that three attempted drone flights were made near the airport on Friday morning and that “at least one was successful.” It put the number of arrests at 11.

Heathrow’s own website said runways and taxiways remain open and operational and that the airport is working with authorities to carry out “dynamic risk assessment programs” to guarantee safety. Drone mitigation and detection systems are being used, it said.

Activists planned to use the drones to disrupt flights and highlight an expected increase in greenhouse gas emissions from a planned third runway at the hub. Heathrow Pause had said it would operate the craft inside the airports’s 5-kilometer (3.1-mile) exclusion zone.

Heathrow earlier this year overcame a legal bid by environmental groups to block construction of a third runway it says is needed to compete with rival hubs. Heathrow Pause had said it would give an hour’s notice before each drone protest, keep flights at a height of 6 feet, and avoid flight paths.

Hundreds of services were cancelled at London Gatwick airport last December following reports of drone sightings close to the runway. Arrests were made but no one was charged in connection with the incidents.

The Met police initially said the men arrested Friday had been detained within Heathrow’s perimeter fence, before explaining later that they’d been held outside and that there was “no breach of airport security.”

To contact the reporter on this story:
Christopher Jasper in London at [email protected]

To contact the editors responsible for this story:
Anthony Palazzo at [email protected]
Andrew Noël, Tom Lavell