WikiLeaks reported that its founder, Julian Assange, has been released from Belmarsh Prison, where he spent 1,901 days.
The High Court in London released him on bail and he has already departed the UK from Stansted Airport, AFP revealed.
Assange previously agreed to plead guilty to breaching US espionage laws, allowing him to avoid US prison and return to Australia.
Since 2010, Assange has faced legal challenges over the publication of classified US documents, and in 2019 he was arrested after Ecuador refused to extend his asylum.
He has since been fighting extradition, sparking global debates about freedom of speech.
Australian-born Assange, 52, is fighting extradition to the US, where he is wanted on 18 charges, almost all under the Espionage Act, related to WikiLeaks' release of classified US documents - the biggest such breach in security in US military history.