"Military capability" deployed to counter illegal drone flights at Gatwick Airport has been withdrawn, the Ministry of Defence has confirmed.
The Army was deployed as hundreds of flights were cancelled on 20 December following repeated drone sightings.
Gatwick said it had spent £5m to prevent future attacks, but would not comment on the nature of the system.
Sussex Police said no arrests have been made since a couple were released without charge on 23 December.
More than 140,000 passengers were affected by cancellations and delays during the 36 hours of chaos.
Following a further sighting on 21 December, the airport said the "military measures" had provided "the reassurance necessary that it is safe to reopen".
It is believed that the Israeli-developed Drone Dome system, which can jam communications between the drone and its operator, was brought in.
A £50,000 reward for information has been issued by Crimestoppers, which said it had "passed on close to 30 pieces of information to law enforcement within the first 24 hours".
A suggestion by a senior Sussex police officer that there may have been no drones was later dismissed as a "miscommunication".
The force said it was investigating "relevant sightings" from 115 witnesses - 93 of whom it described as "credible" - including airport staff, police officers and a pilot.
Chief Constable Giles York had said some of the drones spotted may have belonged to the police and caused confusion. Read more