FAKE MOBILE PHONE MASTS are being used to snoop on Londoners' phone conversations, according to a report on Sky News.
A Sky News investigation has found that communications in the capital city are being intercepted using 'Stingray' devices that mimic mobile phone masts in order to listen in on users' calls without their knowledge.
The surveillance technology is used by police agencies worldwide to target the communications of criminals, but it also collects the data of all other phones in the area.
The news outlet used a system made by German security company GMSK Cryptophone to look for signs of Stingray, or International Mobile Subscriber Identity (IMSI) catchers, across London over a three-week period.
The investigation discovered more than 20 instances of Stingray activity, and Sky has published its full findings online.
GMSK Cryptophone CEO Bjoern Rupp said: "The abnormal events that Sky News had encountered can clearly be categorised as strong indicators for the presence of IMSI catchers in multiple locations."
Commenting on the investigation's findings, Eric King, deputy director of Privacy International, said that this is the first proof of the surveillance technology being used in the UK.
"With IMSI catchers, it's very difficult for them to be used in a targeted manner. In an urban space, thousands of people's mobile phones would be swept up in that dragnet. What they do with that data, we don't know," he said.
"We know police have been using them for years, but this is the first time that it's been shown that they're being deployed in the UK."
The Met Police didn't deny its use of the technology, instead hinting that the technology is in use.
Met commissioner Bernard Hogan-Howe, the UK's most senior police officer, said: "We're not going to talk about it because the only people who benefit are the other side, and I see no reason in giving away that sort of thing.
"If people imagine that we've got the resources to do as much intrusion as they worry about, I would reassure them that it's impossible."
Keith Bristow, director-general of the National Crime Agency, added further weight to this.
"Some of what we would like to talk about to get the debate informed and logical, we can't because it would defeat the purpose of having the tactics in the first place," he said.
"Frankly, some of what we need to do is intrusive, it is uncomfortable, and the important thing is that we set that out openly and recognise there are difficult choices to be made."
But with the Met failing to confirm or deny, it's unclear exactly who is using Stingray devices - be it police forces, intelligence agencies, foreign governments, private companies or criminals.
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