NSA Christmas gift: 12 yrs of surveillance data

In a separate 2013 document, the agency identified several instances where data was mishandled by unknown personnel. According to the entry, a file with "raw [signal intelligence] was improperly uploaded. Many of the breaches were attributed to lackadaisical data security, or unclear instructions that resulted in U.S. citizens accidentally having their privacy violated by the agency's acts.

In a lengthy preamble, the NSA took pains to state any monitoring of U.S. citizens was the result of "unintentional technical or human error."

The agency added that in those cases where a breach was intentional, "a thorough investigation is completed, the results are reported to the IOB and the Department of Justice as required, and appropriate disciplinary or administrative action is taken."

Still, the disclosures are unlikely to alleviate concerns about civil liberties that have reached a boil since last year, when NSA contractor Edward Snowden exposed a sprawling network of classified surveillance activities.

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NSA Christmas gift: 12 yrs of surveillance data