The NSA's three types of cable interception programs

Last week The Washington Post reported that the National Security Agency is tapping into Google and Yahoo internal networks by intercepting communications from the private links between their data centers. The NSA and the office of Director of National Intelligence James R. Clapper criticized the story.

Today The Post answers some of the questions they raised in an explanatory story and offers additional evidence drawn from documents provided by former NSA contractor Edward Snowden. The documents do not tell the whole story, because our report depended in part on interviews with public and private sector sources. But these slides demonstrate that the NSA, working with the British GCHQ, intercepted information it could only have found inside the Google and Yahoo "clouds," or private networks.