Court filing submitted in August mentions the existence of criminal charges against someone named ‘Assange’.

WikiLeaks founder Julian Assange, who is considered a wanted man in the United States for the publication of several classified documents, has been charged in secret by US authorities, according to a report by the Washington Post.

The court filing, which prosecutors say was submitted by mistake, asked a judge to seal documents in a criminal case against someone named “Assange”. The filing carried markings indicating it was originally filed in a US District Court in Alexandria, Virginia in August.

The exact nature of the charges against Assange was not immediately known, but the US officials have previously acknowledged that federal prosecutors based in Alexandria have been conducting a lengthy criminal investigation into WikiLeaks and its founder.

“SCOOP: US Department of Justice ‘accidentally’ reveals existence of sealed charges (or a draft for them) against WikiLeaks’ publisher Julian Assange in apparent cut-and-paste error in an unrelated case also at the Eastern District of Virginia,” Wikileaks posted on Twitter.

SCOOP: US Department of Justice "accidentally" reveals existence of sealed charges (or a draft for them) against WikiLeaks' publisher Julian Assange in apparent cut-and-paste error in an unrelated case also at the Eastern District of Virginia. https://t.co/wrjlAbXk5Z pic.twitter.com/4UlB0c1SAX — WikiLeaks (@wikileaks) November 16, 2018

Since June 2012, Assange has been residing at the Ecuadorian embassy in London after he breached bail in relation to sexual assault allegations he faced in Sweden.

The 47-year-old has always denied the allegations, and his supporters claim the accusations were an attempt to possibly extradite him to the US, where he could face charges over WikiLeaks’ publication of classified military and diplomatic documents.

Swedish authorities dropped their investigation into the case last year and withdrew a European arrest warrant.

But British police have said they still intend to arrest Assange if he leaves the embassy because he broke his conditions for bail by taking refuge there.

Before the 2016 US presidential elections, his website published a trove of private documents from the Democratic National Committee and John Podesta, campaign chairman for presidential hopeful Hillary Clinton.

Clinton has said that it contributed to her failure to win the presidency.