Fleet of mysterious drones spotted flying over rural Colorado, Nebraska

LINCOLN COUNTY, Colo. -- Multiple government agencies are trying to determine why mysterious drones have been spotted flying over parts of rural Colorado and Nebraska.

At the moment, nobody seems to know -- or wants to admit -- who owns and operates these unmanned aerial vehicles.

In the small town of Sterling, Colorado, located about 120 miles northeast of Denver, drone sightings are a nightly affair.

Resident Kimberley Hartford said she saw five drones on her late-night drive home from work.

"People said it's the North Koreans. I've heard that it's like, some alien invasion, drug enforcement," she told Good Morning America. "I have no idea."

Some said airplanes are being mistaken for drones, while others said they may be checking oil fields for leaks or inspecting powerlines.

Police in Lincoln County, where Sterling is located, said the department has observed five to 10 drones per night in a 25-mile radius. Reports of sightings started around Dec. 17.

Officials said the drones aren't breaking the law, but they are concern over privacy and drone collisions.

On Monday, local, state and federal agencies are coming together in Brush, Colorado, for a closed-door meeting with the FAA.

Meanwhile, local officials are reminding residents that shooting drones out of the sky is illegal.