Since before Christmas, sheriff’s departments in the region have been bombarded with reports of large drones with blinking lights and wingspans of up to 6 feet flying over rural towns and open fields. The drones have unnerved residents, prompted a federal investigation and made international news, even though they may be perfectly legal. And still, they remain unexplained.

“In terms of aircraft flying at night and not being identified, this is a first for me personally,” said Sheriff James Brueggeman of Perkins County, Neb., who has worked in law enforcement for about 28 years and who saw the drones while on patrol Tuesday night.

He said he had heard rumblings about people wanting to shoot down a drone, and had urged residents to report the sightings to law enforcement instead. “I think it’s kind of a joke, but you have to remember the part of the country we live in,” the sheriff said. “People here don’t like their privacy to be invaded.”