The Justice Department of the United States is acquiring data from mobile phones by using devices known as "dirtboxes," which are deployed on airplanes.
The high-tech operations, reported by the Wall Street Journal, targets criminals and suspects. However, a huge number of innocent people are also being affected, according to sources that are familiar with the matter.
The U.S. Marshals Service program, which gained full functionality around 2007, controls Cessna airplanes from no less than five airports in metropolitan areas, with a range of flight that covers most of the population of the United States.
The planes carry "dirtboxes," known as such due to the initials of the unit of Boeing that manufactures them, namely Digital Receiver Technology. These devices are capable of mimicking the cell towers of telecommunications companies, tricking mobile phones into reporting the unique registration data that each device holds.
The devices only measure two feet, but they are capable of retrieving information from tens of thousands of mobile phones during a single flight. The information allows investigators to obtain the identifying information of the mobile phones, along with the general location of their users.
The sources would not discuss how often and how long the flights are. However, they did reveal that the flights occur regularly.
Mobile phones automatically connect to the strongest and nearest cell tower signal. The "dirtboxes" identify themselves as cell towers that fit this description, forcing all mobile phones within its range to connect to them and send their unique registration data.
Even if the mobile phone uses encryption, such as those used in Apple's iPhone 6, the process is not prevented.
According to the sources, the devices are able to determine the mobile phones that belong to the individuals being targeted by the operations, then discards the information that it obtained from the mobile phones of non-suspects.
The dirtboxes are also able to briefly cause interruptions on calls. The sources say the authorities have implemented measures to minimize potential harm, such as modifying the software to prevent interruption of any 911 emergency calls.
An official from the Justice Department neither confirmed nor denied the existence of such operations. The official, however, did say that discussing such matters would enable criminals and foreign entities to discover the surveillance capabilities of the United States, and that agencies under the Justice Department operate under compliance with federal law.
The program would be the latest example of how the U.S. carries out surveillance measures within the country. It works similarly to how the National Security Agency retrieves millions of phone records of Americans, collecting massive amounts of data, even when the agency is only looking to find one person.
The government argued that collected phone records is a minimally invasive approach to search for potential terrorists in the country.