When groups of sinister drones began hovering over homes in America’s Midwest, the FBI, US Air Force and 16 police forces set up a task force. But the drones vanished. Did they even exist? Amelia Tait investigates
List of unmanned aerial vehicles - Wikipedia
It's Creepy': Unexplained Drones Are Swarming by Night Over Colorado - The New York Times
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Dramatic Video Shows US Navy's Most Advanced Warship 'Harassed' By Unidentified Drone Swarms
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Drone swarms: FBI investigating swarms of drones in at least three states including Colorado, Nebraska and Kansas - CBS News
Mystery as large 'creepy' drones swarm over Colorado and Nebraska each night leaving cops and FAA baffled – The Sun
Colorado drone mystery sightings finally might be solved, Military
List of unmanned aerial vehicles - Wikipedia
US wants first drones that can kill people truly independently
Colorado drone mystery sightings finally might be solved, Military
Mystery as large 'creepy' drones swarm over Colorado and Nebraska each night leaving cops and FAA baffled – The Sun