The Government Communication Headquarters (GCHQ), the British surveillance agency, coordinated with the U.S. National Security Agency to collect and store webcam images of Yahoo chat users, according to the latest Edward Snowden leak published by The Guardian.
Through a program called Optic Nerve, the agencies collected still webcam images from millions of users, including those suspected of no wrongdoing. According to the British news organization, within just six months during 2008, the agencies collected images from more than 1.8 million different Yahoo accounts from around the world. Of those pictures collected, 3 to 11 percent were sexually explicit, The Guardian reports.
"GCHQ does not have the technical means to make sure no images of UK or US citizens are collected and stored by the system, and there are no restrictions under UK law to prevent Americans' images being accessed by British analysts without an individual warrant," the news outlet wrote.
When approached by the The Guardian, Yahoo reportedly "reacted furiously" to the news, denying having ever heard of the program. The company condemned the operation, saying they considered it to be "a whole new level of violation of our users' privacy."
The program, which began as a prototype in 2008 and was active as of 2012, saved one image every five minutes from the users' feeds and was used for automated facial recognition experiments, to monitor current targets and detect new ones.
"Face detection has the potential to aid selection of useful images for 'mugshots' or even for face recognition by assessing the angle of the face," one document read, according to The Guardian. "The best images are ones where the person is facing the camera with their face upright."