In a fresh crackdown against drones, the Federal Aviation Administration has issued a notice barring UAV flights near the Department of Energy's nuclear research facilities.

The ban, issued on 18 December, will come into effect after 10 days and restrict drone operations over 7 DOE sites that include Hanford, a mostly decommissioned nuclear production complex in Washington, and Pantex, America's primary nuclear weapons assembly and disassembly facility in Texas.

Other sites on the list include the Los Alamos National Laboratory, Idaho National Laboratory, Savannah River National Laboratory, Y-12 National Security Site, and Oak Ridge National Laboratory.

The aviation agency has agreed with the DOE to restrict drone flights up to 400 feet within the lateral boundaries of these sites. Any operator violating the restrictions could face enforcement action, including criminal charges as well as civil penalties.

However, certain exceptions might be made giving operators the liberty to fly their vehicles in the proximity of a site with suitable approvals from the facility in question or the FAA itself.

Over the past few years, the use of unmanned drones has not only sparked fears of collision with civilian planes but also situations where people deploy the vehicles to fly drugs or phones into prisons or carry out air strikes.

The FAA says the move has come in response to "concerns about unauthorised drone operations" from several national security and law enforcement agencies. However, the exact reason behind these restrictions still remains unknown.

The agency already has restrictions in place banning drone flights over military bases and popular Department of Interior sites that include several large dams and national landmarks.