In a repeat of the situation at London’s Gatwick last month, Heathrow airport has ceased departures after sightings of a drone.
Echoing the drama that caused hundreds of thousands to face delays right before Christmas, the airport has closed its northern runway, while at the time of writing, the other remains open.
The airport’s Twitter account posted:
We are responding to a drone sighting at Heathrow and are working closely with the Met Police to prevent any threat to operational safety.
As a precautionary measure, we have stopped departures while we investigate. We apologise to passengers for any inconvenience this may cause.
Scotland Yard said it "received reports of a sighting of a drone in the vicinity of Heathrow airport" at about 5.05pm, and that officers are currently investigating the scenario.
Users took to Twitter to share pictures live from the scene. One claimed there was a police helicopter over the runway.
Meanwhile, Transport Secretary Chris Grayling said the military was "preparing to deploy the equipment used at Gatwick at Heathrow quickly should it prove necessary".
In response to the initial crisis at Gatwick, Heathrow was said to be testing bazookas in case of copycat incidents.
It follows the announcement that drones will now be required to stay even further away from airports.