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It’s the sort of thing that makes you want to hide in a cave with a tin foil hat: a new report reveals that the Justice Department is using airplanes to scan the cell phone data of suspected criminals, and anyone who might be standing near them.

According to the Wall Street Journal, the surveillance system works by strapping a two-foot-square device to Cessna planes operating out of at least five metropolitan airports around the country. As the planes fly overhead, they lock onto the cellphones of suspects and innocent people alike.

The devices, known colloquially as “dirtboxes,” work by imitating cell phone towers and tricking telephones into connecting to them, which in turns provides the location of the phone user. The devices are even capable of collecting call and data information from the phones, according to the Journal. This technique allows investigators to by-pass the slower process of working with phone carriers to collect information via their towers.

If the account is correct, the system amounts to an airborne expansion of the controversial use of sting-rays, which are mobile devices that collect cell phone data, and are reportedly in wide-use by law enforcement units around the country.

While the U.S. reportedly uses airplanes to capture cell phone signals on overseas battlefields, the use of this technique over American cities represents a further expansion of persistent surveillance tactics, such as PRISM or the NSA’s collection of data from phone carriers that was reported in 2013 by former NSA contractor Edward Snowden.

The government appears to believe the aerial program surveillance is legitimate, according to the Journal, because, while bystanders’ phone data is ingested, investigators “let go” of phones not belonging to suspects. It’s unclear what exactly this means, or whether the program retains the data of innocent people.

The government is reportedly obtaining court orders to deploy the aerial surveillance but such orders, if they exist, have so far remained sealed.