Snowden Employed Sophisticated Techniques to Cover His Digital Trail

The U.S. government's efforts to determine which highly classified materials leaker Edward Snowden took from the National Security Agency have been frustrated by Snowden's sophisticated efforts to cover his digital trail by deleting or bypassing electronic logs, government officials told The Associated Press.

http://www.theblaze.com/stories/2013/08/24/snowden-employed-sophisticated-techniques-to-cover-his-digital-trail/