By Kim Zetter

The Intercept

Since May, as protesters around the country have marched against police brutality and in support of the Black Lives Matter movement, activists have spotted a recurring presence in the skies: mysterious planes and helicopters hovering overhead, apparently conducting surveillance on protesters. A press release from the Justice Department at the end of May revealed that the Drug Enforcement Agency and U.S. Marshals Service were asked by the Justice Department to provide unspecified support to law enforcement during protests. A few days later, a memo obtained by BuzzFeed News offered a little more insight on the matter; it revealed that shortly after protests began in various cities, the DEA had sought special authority from the Justice Department to covertly spy on Black Lives Matter protesters on behalf of law enforcement.

Although the press release and memo didn’t say what form the support and surveillance would take, it’s likely that the two agencies were being asked to assist police for a particular reason. Both the DEA and the Marshals possess airplanes outfitted with so-called stingrays or dirtboxes: powerful technologies capable of tracking mobile phones or, depending on how they’re configured, collecting data and communications from mobile phones in bulk.

Stingrays have been used on the ground and in the air by law enforcement for years but are highly controversial because they don’t just collect data from targeted phones; they collect data from any phone in the vicinity of a device. That data can be used to identify people — protesters, for example — and track their movements during and after demonstrations, as well as to identify others who associate with them. They also can inject spying software onto specific phones or direct the browser of a phone to a website where malware can be loaded onto it, though it’s not clear if any U.S. law enforcement agencies have used them for this purpose.

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