Edward Snowden, the exiled US whistleblower, has joined Twitter and is following just one account: the National Security Agency (NSA)
A former NSA employee, Snowden has been a fugitive from the US since leaking information about the spying agency's wide-ranging surveillance and phone-tapping activities.
Within an hour of sending his first Tweet from @Snowden he picked up over 100,000 followers.
His bio states: "I used to work for the government. Now I work for the public."
Snowden, who has been living under asylum in Russia since leaking details of the NSA's then-secret surveillance programmes in 2013, is now a director of the Freedom of the Press foundation which supports independent journalism.
Some have criticised Snowden for releasing sensitive information without regard to the effect on American national security.
In response to such criticism - put forward to him by scientist Neil deGrasse Tyson - Snowden replied: "Hero, traitor - I'm just a citizen with a voice."
Can you hear me now?— Edward Snowden (@Snowden) September 29, 2015