Image of PRISM slide from The Washington Post

Apple, Google, Yahoo, Microsoft and Facebook are among companies that have denied giving the federal government direct access to their servers in order to gain access to the private communications of citizens.

The denials are in response to a set of slides obtained by The Washington Post and The Guardian, which revealed a training manual for a secret surveillance program called PRISM, though which the government allegedly taps directly into the servers of these Silicon Valley companies in order to spy on terrorists.

Here is more from The Washington Post:

The NSA prides itself on stealing secrets and breaking codes, and it is accustomed to corporate partnerships that help it divert data traffic or sidestep barriers. But there has never been a Google or Facebook before, and it is unlikely that there are richer troves of valuable intelligence than the ones in Silicon Valley.

Equally unusual is the way the NSA extracts what it wants, according to the document: ‘Collection directly from the servers of these U.S. Service Providers: Microsoft, Yahoo, Google, Facebook, PalTalk, AOL, Skype, YouTube, Apple.’