The man responsible for one of the biggest breaches of security in the history of American intelligence has revealed his identity.
Edward Snowden, 29, a former CIA computer expert, leaked information on clandestine surveillance operations that monitor computer and telephone networks worldwide.
Last week, The Guardian and The Washington Post reported that US agencies gathered millions of phone records and monitored internet data under a programme called Prism.
The papers said the National Security Agency (NSA) tapped directly into the servers of nine internet companies including Facebook, Google, Microsoft and Yahoo! to track online communication. The companies deny giving the government access, the BBC reports.
Prism is said to give the NSA and FBI access to emails, web chats and other communications directly from the servers. The data is used to track foreign nationals suspected of terrorism or spying. The NSA is also collecting telephone records of American customers, but not recording the content of their calls.
Prism was reportedly established in 2007 and was authorised under changes to US surveillance laws passed under President George W Bush and renewed in 2012 under President Barack Obama.
In a video on the The Guardian's website, Edward Snowden said that American intelligence agencies are subverting the power of government and threatening democracy, and explained why he leaked the information.
"I'm just another guy who sits there day to day in the office who watches what's happening and goes, 'This is something that's not our place to decide; the public needs to decide whether these programmes or policies are right or wrong'.
"And I'm willing to go on the record to defend the authenticity of them and say I didn't change these, I didn't modify the story. This is the truth, this is what's happening - you should decide if we need to be doing it."
Mr Snowden has sought refuge in Hong Kong, where he has been holed up in a hotel since 20 May. He told The Guardian: "I don't want to live in a society that does these sort of things… I do not want to live in a world where everything I do and say is recorded."
When asked what he thought would happen to him, he replied: "Nothing good." He said he chose to go to Hong Kong because of its "strong tradition of free speech" and would ask for asylum in any country that believes in this.
A spokesman for the US Office of the Director of National Intelligence said the matter has been referred to the Department of Justice as a criminal matter.
Mr Snowden is at present employed by defence contractor Booz Allen Hamilton. In a statement, the company said he had been working for them for less than three months. "If accurate, this action represents a grave violation of the code of conduct and core values of our firm," it said.