WikiLeaks founder Julian Assange's former right-hand man has irrevocably destroyed 3500 unpublished files leaked to the whistleblower site including the complete US no-fly list, five gigabytes of Bank of America documents and detailed information about 20 neo-Nazi groups.

Daniel Domscheit-Berg, who left WikiLeaks last year after a falling out with Assange, revealed the document destruction in an interview with Der Spiegel.

WikiLeaks has hit back, accusing Domscheit-Berg of being in bed with US intelligence agencies and of jeopardising the leaking of “many issues of public importance, human rights abuses, mass telecommunications interception, banking and the planning of dozens of neo-nazi groups”.

Along with the thousands of files, Domscheit-Berg also took the entire Wikileaks encrypted submission system with him on his way out to start a rival site, OpenLeaks. It has resulted in WikiLeaks being unable to receive leaked documents online for a year, with the site instead resorting to snail mail via an Australian P.O. Box at the University of Melbourne.

In a translation of the Der Spiegel interview, Domscheit-Berg said he had the files “shredded to ensure that the sources are not compromised”.

A large factor in Assange and Domscheit-Berg falling out was the fear that Assange released the 400,000 classified US documents about the Iraq war too early without taking the time to properly redact names of US collaborators and informants in Iraq.

In his book released this year, Inside WikiLeaks (review), Domscheit-Berg accused Assange of being autocratic and said the reason he took the submission system and unpublished documents was because “children shouldn't play with guns”.

“We will only return the material to Julian if and when he can prove that he can store the material securely and handle it carefully and responsibly,”....