In the latest chapter of the American people vs. the U.S. Justice system, the Wall Street Journal has uncovered a secret program implemented in 2007 that uses planes to take civilian cellphone data.

Here how it works: The U.S. Marshals put a "dirtbox," a two-foot square device, on Cessna airplanes and fly over American soil. The dirbox mimics a cellphone tower's signal, tricking cellphones into giving up unique identifiying information. Encryption, including the security on the iPhone 6, offers no protection from these flyovers.

The planes leave from at least five major airports, and cover most of the U.S population during their flights, Wall Street Journal sources said (paywall).

SEE ALSO: Most NSA-Collected Data Comes From Ordinary Internet Users

The technology can also collect the location of the user within 10 feet and personal data, including text messages and photos, according to the Wall Street Journal (paywall).

The program is allegedly part of a sweep for criminals like drug dealers and murderers, officials said, but collects tens of thousands of civilians' information in the process. 

In response to the WSJ article, the Marshals Service said Friday that it does not keep a database of the general public's data, without confirming whether the program existed.

Read more at the BBC, or The Wall Street Journal with a subscription.

Reach Web Producer Arielle Samuelson here.