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As others have pointed out, this is a clever way of implying that Snowden is the source for the story. Unfortunately for The Independent, Snowden is still very much alive and capable of issuing statements, which is exactly what he did:
I have never spoken with, worked with, or provided any journalistic materials to the Independent.
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Snowden himself offers an explanation:
It appears that the UK government is now seeking to create an appearance that the Guardian and Washington Post's disclosures are harmful, and they are doing so by intentionally leaking harmful information to The Independent and attributing it to others. The UK government should explain the reasoning behind this decision to disclose information that, were it released by a private citizen, they would argue is a criminal act.Is he right? Who knows. One thing is certain: The Independent is being incredibly manipulative and secretive about its source, and that fact alone should be deeply troubling to everyone. There is a Second Source out there for the NSA leaks, and the only people who know about it -- The Independent -- don't want you to know about it. Why?