Ever since an August report in Popular Science revealed the existence of a series of "Interceptor" cell towers across the US, there's been a scramble for information on exactly what these mysterious towers actually are. There are suggestions that the cell towers are the work of criminal gangs, a surveillance tool by the FBI, or even that they belong to foreign spies.
Here's everything we know about the mysterious cell towers so far.
How were the towers first uncovered?
The first news of the mysterious towers came from a press release for a high-end smartphone — they were not uncovered through a research paper or security researcher's blog as one would normally expect.
A map of the "Interceptor" cell towers was first published by retailer ESD America as an example of "what the CryptoPhone can do that less expensive competitors cannot," Popular Science reported. The GSMK Cryptophone 500 is a heavily-modified Samsung Galaxy SIII. It's marketed as a secure alternative to normal mobile phones with a cost upward of $3,500.
Since then, ESD America has been the source of every story about the fake cell towers, gradually releasing details of the towers as the phone's owners discover new locations.
How can a fake cell phone tower be used to intercept your call?
If your phone connects to a fake cell tower, whoever operates the device can listen to your calls, intercept your text messages, and send fake text messages to your phone. It's also possible to monitor and track the physical location of a mobile phone using a hacked cell tower, meaning that so-called "Interceptor" towers can be used to follow people as they travel in the area of the cell tower.