Mystery Deepens Over Cell 'Interceptors' Found Near White House, Senate

A company that sells secure mobile phones has found more than a dozen "interceptor" cellphone towers in Washington, D.C., some of them located near the White House and the U.S. Capitol.

Les Goldsmith, CEO of ESD America, the makers of the secure Cryptophone 500, said it is unclear who installed the units.

"It’s highly unlikely that federal law enforcement would be using mobile interceptors near the Senate. My suspicion is that it is a foreign entity," he said.

The devices, which aren't really towers and can be as small as a suitcase, can listen in on phone calls. VentureBeat, which first reported on the devices, said two kinds of interceptors have been found: "IMSI Catchers, which can steal subscriber info for later monitoring, and GSM Interceptors, which can listen into calls." Some devices do both.

What's more, the devices can load spyware onto a mobile device -- a cell phone or tablet -- before passing off a victim’s call to a real network.

ESD America said it has found 15 in downtown Washington and three in Northern Virginia. And EDS said some 45 devices have been found outside the D.C. area. The Federal Communications Commission announced last month it is investigating the use of network interceptors by gangs and foreign intelligence agencies. But so far, no one knows who is planting or operating them.