Wired News: Whistle-Blower's Evidence, Uncut:

I [Former AT&T technician Mark Klein] wrote the following document in 2004 when it became clear to me that AT&T, at the behest of the National Security Agency, had illegally installed secret computer gear designed to spy on internet traffic. At the time I thought this was an outgrowth of the notorious Total Information Awareness program, which was attacked by defenders of civil liberties. But now it's been revealed by The New York Times that the spying program is vastly bigger and was directly authorized by President Bush, as he himself has now admitted, in flagrant violation of specific statutes and constitutional protections for civil liberties. I am presenting this information to facilitate the dismantling of this dangerous Orwellian project.

In 2003 AT&T built "secret rooms" hidden deep in the bowels of its central offices in various cities, housing computer gear for a government spy operation which taps into the company's popular WorldNet service and the entire internet. These installations enable the government to look at every individual message on the internet and analyze exactly what people are doing. Documents showing the hardwire installation in San Francisco suggest that there are similar locations being installed in numerous other cities.

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