Sadly this seems to be a deliberate act, an environmental protest or something else to disrupt a major airport. Attaching the lights was to attract attention.
This incident has infuriated many responsible drones owners whether for business or pleasure who abide by the rules and fly responsibly.
Hopefully, the culprits will be caught, the cost to the airlines and the airports if horrific but if I were a passenger who has been affected I would seek redress via the small claims court against whoever is responsible. A few thousand claims for lost business or inconvenience will make others think twice.