Amazon and several other retailers are the target of an ongoing investigation by the Federal Communications Commission for selling wireless signal jammers and other unlawful electronic devices.
In an unusual statement acknowledging the investigation, spokesperson Will Wiquist told Fortune the FCC had “several ongoing investigations into retailers, including Amazon, for potential violations of Commission rules related to the marketing and sale of equipment without proper FCC authorization.”
The FCC did not disclose which other retailers it is investigating.
At issue are the sale of signal jammers, which can block or disrupt everything from cell phones to GPS systems to WiFi signals. Those products are illegal to use, sell or even advertise in the U.S. Authorities note they can prevent people from making 9-1-1 calls and security experts note thieves can use them to nullify wireless security cameras, which are popular for home security.
Even local police forces are prohibited from using the technology. (Federal law enforcement officials can, under certain circumstances, the FCC says.)
The move comes following an NBC report which found nine independent Amazon sellers offering jamming devices. Amazon has since removed those listings and told NBC it has policies in place prohibiting the sale of jamming devices.
Amazon did not respond to Fortune’s request for comment about the investigation.
Even if the FCC is able to stop the retail sale of signal jammers, there is a flourishing online culture that revolves around the technology. Select websites show how to build a jammer that can easily be hidden, though you’ll need some technical knowledge to successful assemble the device.