The U.S. government is reportedly using spy airplanes equipped with special military-grade snooping equipment to eavesdrop on cell phone information from millions of smartphone users in U.S, according to a new report.





This little device, nicknamed "Dirtbox", is being used to mimic mobile phone tower transmissions from the sky and gather data from millions of mobile phones, helping the US Marshals Service track criminals while recording innocent citizens' information.





Dirtbox causes smartphones to transmit back the users' location, registration information and identity data – uniquely identifying IMEI numbers stored in every mobile device, The Wall Street Journal The purpose of the device is supposedly to track a specific target, but if active, all mobile devices in the particular area will respond to the signal. Thecauses smartphones to transmit back the users' location, registration information and identity data – uniquely identifying IMEI numbers stored in every mobile device, The Wall Street Journal reported

The name Dirtbox is given after the initials of Digital Receiver Technology, Inc. (DRT), a Boeing Company subsidiary that allegedly manufactures these devices. These two-foot-square snooping devices imitate cellphone towers and thus make contact with all handsets in the range.

"DRT has developed a device that emulates a cellular base station to attract cell phones for a registration process even when they are not in use," Boeing said in a 2010 filing [PDF].

The operation began in 2007 and according to the WSJ, a "source familiar with the program" said that these devices are fitted onto Cessna aircraft and fly from at least five metropolitan airports in the US. The planes cover the majority of the US population.





IMSI (International mobile subscriber identity) catchers or Stingrays, that is in use by over 46 agencies including the law enforcement, the military, and intelligence agencies across 18 states and Washington, D.C. for more than a decade. The dirtboxes operate in the same way as the so-called mobile phone surveillance tool, that is in use by over 46 agencies including the law enforcement, the military, and intelligence agencies across 18 states and Washington, D.C. for more than a decade.





StingRays are common surveillance devices that allow law enforcement to mimic a cell phone tower, and track users position who connect to it, and sometimes even intercept calls and Internet traffic, send fake texts, install spyware on a phone, and determine precise locations.





Both Stingrays and Dirtboxes make use of "off-the-shelf" components to gather mobile phones' International Mobile Subscriber Identity (IMSI) which is a unique code to each device. They can be used to track individuals' movements via their mobile phone devices but work indiscriminately, hovering up information from a general area.





The US Department of Justice – which oversees the marshal service – has neither confirmed nor denied the existence of the Dirtbox program, but anonymous sources familiar with their use said the flying spies-in-the-sky were technically above board.





The WSJ quotes one source as stating, "What is done on US soil is completely legal….., Whether it should be done is a separate question."