It could also have been they were helping the police track down someone, who would bother to help if they knew their faces would be in the media ? could be very dangerous.

So who was the bloke who was, apparently, witnessed frantically packing away a drone?

Asked about speculation there was never such a drone flown over the airport, Detective Chief Superintendent Jason Tingley told the BBC: "Of course, that's a possibility. We are working with human beings saying they have seen something.

"Until we've got more clarity around what they've said, the detail - the time, place, direction of travel, all those types of things - and that's a big task."

However, Mr Tingley also said one of the "working theories" was that a damaged drone found close to the airport in Horley was responsible for causing the disruption.

"Always look at it with an open mind, but actually it's very basic common sense that a damaged drone, which may have not been there at a particular point in time has now been seen by an occupier, a member of the public, and then they've told us, 'we've found this'.

"Then we go and forensically recover it and do everything we can at that location to try and get a bit more information."

This is including working through information relating to "persons of interest", as well as investigating more than 67 drone sightings and forensically examining the damaged drone.