The UK spy agency, GCHQ reportedly collected millions of Yahoo webcam images, including a large number of sexually explicit pictures.
Classified documents related to the alleged mass surveillance programmes, headed by GCHQ and its US counterpart, the NSA, have revealed that the agency's Optic Nerve programme indiscriminately collected still images of Yahoo webcam chats in bulk and saved them to agency databases.
According to the Guardian, the documents dating between 2008 and 2010 revealed that in one six-month period in 2008 alone, the agency collected webcam imagery, which included a substantial amount of sexually explicit communications from more than 1.8 million Yahoo user accounts globally.
Yahoo denied having prior knowledge of such an interception and accused the agencies of "a whole new level of violation of users' privacy".
The report said that the 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 documents revealed by NSA whistleblower Edward Snowden further pointed that rather than collecting webcam chats in their entirety, the Optic Nerve programme saved one image every five minutes from the users' feeds, partly to comply with human rights legislation, and also to avoid overloading GCHQ's servers.
Meanwhile, GCHQ insisted all of its activities were necessary, proportionate, and in accordance with UK law.
