NBC News reported that online retailers and drone technology companies are marketing radio frequency jammers as drone deterrence or privacy tools, bypassing laws that prohibit the sale of such devices in the United States.

The warning issued by the Federal Communications Commission (FCC) says signal jamming devices can block emergency calls and pose a serious risk to public safety communications, as well as interfere with other forms of daily communication and air navigation systems.

"The use of telephone jammers, GPS jammers, or other signal jamming devices designed to intentionally block, interfere with, or interfere with authorized radio communications violates federal law," the FCC said. "There are no exemptions for use in businesses, classrooms, homes or vehicles. Local law enforcement agencies do not have independent powers to use jamming devices; With certain limited exceptions, use by federal law enforcement agencies is authorized under applicable statute."

The FCC's warning also states that "it is illegal to advertise, sell, distribute, import, or otherwise market interfering devices to consumers in the United States."

But NBC reported that Amazon third-party sellers, independent online stores based in China, and small domestic companies specializing in drone-related equipment flouted the law. The FCC told NBC that it is investigating the sale of jammers, including on Amazon.

As part of its investigation, NBC interviewed the CEO of an American company that offers portable anti-drone RF jamming devices online. The CEO told NBC that the devices are easy for consumers to buy if they have the money, but they are mainly seeing interest from large corporations and government agencies as they prepare for domestic drone terrorism.