A group of 40 campaigners gathered outside the American embassy in London on Saturday to protest against the incarceration of a US Army private accused of leaking information to whistleblowing website WikiLeaks.
Bradley Manning, 24, is charged with passing classified data and delivering national defence information to an unauthorised source.
It is claimed he sent hundreds of thousands of diplomatic cables and war logs to Julian Assange's Wikileaks website while working as an intelligence analyst in Iraq.
Manning could be sentenced to life imprisonment if convicted of the most serious offence, aiding the enemy.
On Saturday, protesters gathered in front of the heavily guarded Grosvenor Square building for more than an hour bearing Free Bradley Manning placards.
Ben Griffin, 34, a former SAS soldier and founding member of Veterans For Peace UK, addressed the crowd after observing a 30-minute silent vigil.
He said: "The most significant piece of resistance to the ongoing wars in Iraq and Afghanistan came when a young soldier released information that the US and UK governments would rather we did not know about.
"Among the files released through Wikileaks were the Afghan War Diaries which showed the day-to-day ritual killing and torture that has been going on in Afghanistan for years.
"Then the Iraq War Logs were released. As a result of those logs we found out about thousands of people killed in Iraq by US and UK troops that we did not know about.
"Through the diplomatic cable release we now know about the sneaky little deals with other governments so we do not know the reality of the wars.
"As a result of these leaks a young soldier has spent years in prison and still has not come to trial.
"As a result of action around the world the US military was forced to move him from Quantico (Virginia), to Fort Leavenworth (Kansas).
"That guy is still being held and for the last six months we've been coming here when Bradley Manning has been taken to a pre-trial hearing, when the military decide what is going to be allowed to come out in his case and what is not, and standing in solidarity."
Among the dozens of protesters were several wearing the V For Vendetta mask that has become associated with the hacking group Anonymous.
Others carried banners saying "Blowing the whistle on war crimes is not a crime" and "Free Assange, Free Manning, End the war".
One demonstrator who gave her name only as Val, from Bedford, said: "Bradley Manning, I think, is a hero.
"If anybody should have got the Nobel Peace Prize it is him."
Fellow campaigner 38-year-old Glyn Jukes, from Wales, said: "He stands for truth and justice at a time when very few others are."
Another protester, who asked to remain anonymous, said: "I think Bradley Manning should be released.
"I do not think he has morally broken any laws and what he has done will only help society."
After more than an hour outside the US Embassy the group moved to Ecuador's London embassy where Wikileaks founder Julian Assange has been holed up for more than two months.
On Sunday August 20 when Assange appeared on the balcony of the embassy, he called on the US to end its "war on whistleblowers" and demanded the release of Bradley Manning.
Assange described him as a hero and "an example to all of us".