The true extent of the security threat posed by NSA whistleblower Edward Snowden is 'unknown', according to a top government aid, as it is revealed the White House is unsure what secret files he possesses. The revelation came as a new batch of highly classified documents was made public across the internet yesterday, revealing how the U.S. government has collected online data in bulk. Fugitive leaker Mr Snowden, who worked as an undercover computer specialist with the CIA before contracting with the National Security Agency, remains in the transit area of Sheremetyevo Airport, in Moscow. He had been expected to fly to Cuba but has not reportedly left Russia.
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Obama adviser admits they 'don't know' which files Snowden has copied
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Further classified documents have been exposed on U.S. data collection
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NSA leaker Edward Snowden remains in the transit area of Moscow airport after leaving Hong Kong on Sunday
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U.S. demanded Russia extradites him immediately but Putin refused
Russian and foreign journalists continued to monitor the @placeholder, where Snowden is believed to remain at the transit zone.