In a statement announcing the filing, a Justice Department spokesperson said, "The superseding indictment alleges that Assange was complicit with Chelsea Manning, a former intelligence analyst in the US Army, in unlawfully obtaining and disclosing classified documents related to the national defense".
Prosecutors say Assange asked for and received hundreds of thousands of secret government documents including military reports and State Department cables in violation of the act.
The Australian whistleblower, who holed himself up in the Ecuadoran embassy in London for seven years to avoid a British extradition order to Sweden, was arrested by British police on April 11 after Ecuador gave him up. A court in the U.K.is now considering at least two requests for Assange's extradition - from the United States and Sweden - and is not expected to rule on where Assange is headed next until early June.
"Assange is also charged with conspiracy to commit computer intrusion for agreeing to crack that password hash".
Court documents described a series of chats between Assange and Manning in March 2010 in which Assange allegedly encourages Manning a few times to obtain documents.
The Washington Post reported Thursday afternoon that federal prosecutors had brought an superseding 18-count indictment against Assange accusing him of violating the Espionage Act.
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Manning is in custody in Northern Virginia for apparently refusing to cooperate with the U.S. Attorney's Office in the grand jury proceeding that yielded the indictment unsealed on Thursday.
Assange remains in jail in the United Kingdom awaiting the court's decision.
The Trump Administration's decision to charge Assange for attracting - and then publishing - classified material is expected to provoke blowback on First Amendment grounds.
"These unprecedented charges demonstrate the gravity of the threat the criminal prosecution of Julian Assange poses to all journalists in their endeavor to inform the public about actions that have taken by the USA government", said Pollack, Assange's lawyer.
Prosecutors also added a charge related to the disclosure of national defense information that included the unredacted names of human sources in places such as China, Syria, Afghanistan and elsewhere.
He is now serving a 50-week sentence in a London jail for skipping bail when he fled to the Ecuadorean embassy in 2012. UK authorities will decide on his extradition to the United States.
The Justice Department's quick turn-around with the filing of a more substantial indictment against Assange is not surprising. And they say his actions strayed far outside what the First Amendment protects. "Either you are a worthless coward or you defend Assange, WikiLeaks and Journalism".