<p>FORT MEADE, Md., Oct. 15 (UPI) -- The National Security Agency grabs and keeps tens of millions of personal email and instant messaging contact lists of Americans, secret documents indicate.</p><p>The tens of millions of Americans' personal contact lists are among about a quarter-billion lists the NSA harvests each year, senior U.S. intelligence officials told The Washington Post, confirming information in top-secret documents leaked by former NSA contractor Edward Snowden.</p><p>The global spying activity is not authorized by Congress or by the secret intelligence court that oversees foreign surveillance, the officials said.</p><p>That's because the NSA grabs the contact lists overseas, rather than domestically, as messages move across global data links, one senior official told the Post.</p><p><a href="http://www.upi.com/Top_News/US/2013/10/15/NSA-said-to-collect-Americans-email-chat-contact-lists/UPI-93171381818600/">Keep reading...</a></p>