Unidentified drones were observed flying over three Royal Air Force (RAF) bases used by the United States Air Force (USAF) in eastern England.The drones varied in size and configuration, and their activity appeared coordinated.The drones did not disrupt operations or pose a direct threat to personnel, but their nature of activity has raised concerns.Investigations by U.S. and U.K. defense officials are ongoing to determine the origin and purpose of the drones.