Verizon has been providing the National Security Agency with millions of subscribers' telephone records following a secret court order, according to a report.

The order, a copy of which was obtained by The Guardian, requires Verizon to give the NSA the phone numbers, duration, time, routing information and other details for any calls made within the United States or between the United States and other countries. It does not require Verizon to provide a record of actual conversations.

Verizon is specifically prohibited by the order from discussing it publicly. A Verizon spokesperson declined to comment when asked about the order by The Guardian. The National Security Agency, the White House and the Department of Justice also chose not to comment to the newspaper.

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The NSA was granted the authority to collect three months' worth of Verizon subscribers' data beginning April 25 and ending July 19 by the secret Foreign Intelligence Surveillance Court. The FISC traditionally grants or rejects requests for surveillance warrants against suspected foreign agents under the Foreign Intelligence Surveillance Act.

As The Guardian's Glenn Greenwald points out, the Verizon order is unusual in that it gives the NSA the authority to collect Americans' phone records en masse. FISA orders have traditionally been more focused on specific individuals or small groups suspected of terrorism, or other actions threatening the United States' national security.

It's unclear how deep this particular rabbit hole goes: This leaked Verizon document may be the sole FISA order of its breadth and magnitude, or it may be the first publicly seen evidence of a larger government-data-gathering regime potentially involving numerous telecommunications providers. There's no evidence yet, however, that the NSA is collecting data from other providers.

The NSA's Verizon order is the first known instance of the Obama administration monitoring American citizens' communications in bulk. Former president George W. Bush secretly authorized a widespread NSA telephone, Internet and email-monitoring program less than a month after the 9/11 attacks; that program was exposed in 2006.

The Guardian's report, which will run on the newspaper's front page Thursday, is sure to ignite a fresh wave of heated debate over the United States government's decision to monitor citizens who are not suspected of any crime under the banner of national security.

Should the NSA be able to collect citizens' cellphone records based on a secret court order? Share your thoughts in the comments.

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