Julian Assange has refused to be extradited back to the US over allegations he conspired to hack into a classified Pentagon computer.
The WikiLeaks founder appeared at Westminster Magistrates' Court for his first extradition hearing since being carried out of the Ecuadorian embassy in London where he was holed up for nearly seven years.
Assange appeared via video link, dressed in jeans and a light-coloured top in front of a packed courtroom.
He formally refused to consent to his extradition during the hearing which lasted a little longer than 10 minutes.
The 47-year-old said: "I do not wish to surrender myself for extradition for doing journalism that has won many awards and protected many people.”
US prosecutors announced they had filed charges against Assange, including that he conspired to hack highly sensitive information along with Chelsea Manning.
If found guilty and he is extradited, Assange faces up to five years behind bars.
Prosecutors claim Assange helped Manning crack a code, which helped leak classified records to the whistleblowing website.
Classified documents allegedly downloaded included around 90,000 Afghan-war related reports, 400,000 Iraq war-related reports, 800 Guantanamo Bay detainee assessments and 250,000 US State Department cables, the court heard.
Ben Brandon, who worked as a barrister for the US government, said investigators had proof of live chats between Assange and Manning.
Mr Brandon said: “Investigators in the US obtained details of chatroom communications between Ms Manning and Mr Assange in March 2010 from Ms Manning’s computer.”
He said the pair had “engaged in real time discussions regarding Chelsea Manning’s dissemination of confidential records to Mr Assange”.
He added that Assange “actively tried to crack the password (to the classified computer) and encouraged Ms Manning to provide more information”.
Assange was remanded in custody to appear via video link again in the same court on May 30 for a further hearing.
Assange's extradition appearance came a day after he was sentenced to 50 weeks in prison for breaching bail conditions when he failed to surrender to police in 2012.
A group of the Wikileaks founder's supporters gathered both inside and out of the court, as some even blocked the roads nearby Westminster Magistrates' Court.
Lauri Love, whose own extradition ruling was quashed over allegations he hacked US government computers, was among the supporters.
High Court judges ruled Love, who has Asperger's, would be "oppressive by reason of his physical and mental condition”.
The 34-year-old from Suffolk, said he came to court to “keep an eye on the process and make sure that it’s done as fairly as possible”.
He said: “I’ve been through this whole mill so I am supporting Julian in opposing extradition to the US where I think he would, like myself, not have a very strong chance of having a fair trial.
“I know how traumatic this ordeal can be, years of having to be afraid of being taken to another country and treated badly.”