US justice officials are scooping up mobile phone data from unwitting Americans as part of a sophisticated airborne surveillance program designed to catch criminals, the Wall Street Journal reported Thursday.
Small aircraft deployed by the US Marshals Service from at least five major airports have been taking to the skies with "dirtbox" equipment designed to mimic signals from cell towers, according to the Journal.
That in turn tricks mobile phones into revealing unique identifying numbers and general locations, according to the report.
The name "dirtbox" was said to be derived from an acronym of Digital Recovery Technology Inc., the Boeing subsidiary that makes the device.
The range of aircraft in the program covers most of the US population, the Journal reported, citing unnamed sources familiar with the operation.
Details of flights were not given, but they were said to take place regularly with each outing potentially gathering data from tens of thousands of mobile phones.