Northeastern Colorado has been subjected to some strange sightings at night since Christmas week. Now the sightings have spread to Nebraska.

Drones that are approximately 6 feet in length have been sighted in nightly swarms as large as 30 and have been reported across six counties, according to Business Insider.

The drone sightings were first reported by the Denver Post on Dec. 23.

Phillips County Sheriff Thomas Elliott said in the report that he doesn't know who owns the drones or where they're coming from, but he doesn't believe the drones are malicious.

He also believes their formation reveals that the drones are doing a grid search or pattern.

Representatives for the Air Force, the Drug Enforcement Administration, and the U.S. Army Forces Command all said the drones did not belong to their organizations, according to Business Insider.

Currently, there aren't regulations that require identification from drone operators.

If you see a drone, you are urged to NOT shoot them down because they are very flammable and become a self-generated fire until they burn out of their own accord.