The latest charges accuse him of unlawfully publishing the names of classified sources as well as conspiring and assisting ex-Army intelligence analyst Chelsea Manning in accessing classified information.
The charges, contained in an 18-count indictment announced on Thursday, go far beyond an initial indictment against Assange made public last month that accused him of conspiring with Manning to gain access to a government computer, as part of a 2010 leak by WikiLeaks of hundreds of thousands of US military reports about the wars in Afghanistan and Iraq.
The new indictment, which accuses Assange of violating the espionage act, says his actions “risked serious harm” to the US.
It said Assange had “repeatedly encouraged sources with access to classified information to steal and provide it to Wikileaks to disclose”.
“Julian Assange is no journalist,” said assistant attorney general John Demers, the Justice Department’s top national security official. “No responsible actor, journalist or otherwise, would purposely publish the names of individuals he or she knew to be confidential sources, exposing them to the gravest of dangers.”
Assange, 47, is serving a 50-week jail sentence in the UK for breaching bail conditions following his eviction from the Ecuadorian Embassy in April. The US is seeking his extradition.
Manning, meanwhile, who was convicted in military court for providing a trove of classified documents to WikiLeaks, is currently in a northern Virginia jail on a civil contempt charge.
She spent two months in the Alexandria Detention Centre beginning in March after she refused to testify to a grand jury investigating WikiLeaks. That grand jury is sitting in Alexandria, where Assange is charged. She could remain in jail for up to 18 months, the length of the current grand jury’s term.
Manning has said she believes prosecutors want to question her about the same conduct for which she was convicted at her court-martial. She served seven years of a 35-year military sentence before receiving a commutation from then-president Barack Obama.
In response to the indictment, WikiLeaks tweeted: “This is madness. It is the end of national security journalism and the first amendment.”
Kristinn Hrafnsson, editor-in-chief of WikiLeaks, said: “I find no satisfaction in saying ‘I told you so’ to those who for nine years have scorned us for warning this moment would come. I care for journalism. If you share my feeling you take a stand NOW.
“Either you are a worthless coward or you defend Assange, WikiLeaks and Journalism.”
Additional reporting by agencies
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