Julian Assange: "He is the quintessential whistleblower"
Julian Assange, founder of the anti-secrecy organisation Wikileaks, has said the conviction of US Army Private Bradley Manning on spying charges is a "dangerous precedent".
Pte Manning, 25, had admitted leaking thousands of classified documents to Wikileaks but said he did so to spark a debate on US foreign policy.
The leak is considered the largest ever of secret US government files.
He faces a maximum sentence of up to 136 years.
Pte Manning was convicted on Tuesday of 20 charges in total, including theft and computer fraud but was found not guilty on the most serious charge of aiding the enemy.
In addition to multiple espionage counts, he was also found guilty of five theft charges, two computer fraud charges and multiple military infractions.
His sentencing hearing is set to begin on Wednesday. It may be a lengthy process, as both the defence and the prosecution are allowed to call witnesses.
Many will hope the court does make an example of Pte Manning to discourage others from making secrets public, the BBC's North America Editor Mark Mardell reports from Washington.
Mr Assange said the verdicts represented "dangerous national security extremism".
Speaking from the Ecuadorean embassy in London, Mr Assange said: "This has never been a fair trial.
"Bradley Manning isn't guilty of anything in that he's actually very heroic for demanding government transparency and accountability and exposing the American people and the rest of the world to the crimes committed by the American government," he said.
Mr Assange said the only victim in the case had been the US government's "wounded pride".
He said that there were two appeals within the US justice system as well as the Supreme Court. "WikiLeaks will not rest until he is free," Mr Assange said.
Graphic footage Pte Manning appeared not to react as Judge Colonel Denise Lind read out the verdict on Tuesday, but his defence lawyer, David Coombs, smiled faintly as the not guilty charge on aiding the enemy was read.
"We won the battle, now we need to go win the war," Mr Coombs said of the sentencing phase. "Today is a good day, but Bradley is by no means out of the fire."
During the court martial, prosecutors said Pte Manning systematically harvested hundreds of thousands of classified documents in order to gain notoriety.
With his training as an intelligence analyst, Pte Manning should have known the leaked documents would become available to al-Qaeda operatives, they argued.
The defence characterised him as a naive and young soldier who had become disillusioned during his time in Iraq.
His actions, Mr Coombs argued, were those of a whistle-blower.
In a lengthy statement during a pre-trial hearing in February, Pte Manning said he had leaked the files in order to spark a public debate about US foreign policy and the military.
Much of the court martial was spent considering the soldier's intentions as he leaked the documents.
Amnesty International said in a statement the "the government's pursuit of the 'aiding the enemy' charge was a serious overreach of the law, not least because there was no credible evidence of Manning's intent to harm the USA by releasing classified information to WikiLeaks."
But the Democratic and Republican leaders of the US House of Representatives intelligence committee said "justice has been served", in a joint statement after the ruling.
Among the items sent to Wikileaks by Pte Manning was graphic footage of an Apache helicopter attack in 2007 that killed a dozen people in the Iraqi capital Baghdad, including a Reuters photographer.
The documents also included 470,000 Iraq and Afghanistan battlefield reports and 250,000 secure state department cables between Washington and embassies around the world.
Pte Manning, an intelligence analyst, was arrested in Iraq in May 2010. He spent weeks in a cell at Camp Arifjan, a US Army installation in Kuwait, before being transferred to the US.