He is the elusive Scarlet Pimpernel of cyberspace whose website has been behind some of the most remarkable scoops in recent years. But ever since an American soldier was arrested for allegedly leaking video footage of a helicopter attack in Baghdad, Wikileaks' founder, Julian Assange, has been keeping a low profile.
Last night the Australian-born former hacker made his first public appearance in Britain since it emerged that US investigators are looking to speak to him about reports that his organisation had been handed thousands of diplomatic cables by the same person who is thought to have leaked the Apache helicopter video.
Earlier this week the man accused of leaking the video was charged by US military investigators. Private First Class Bradley Manning, a 22-year-old army intelligence analyst who was working in Iraq with high-level security clearance, was arrested after a former-hacker-turned-journalist reported him to the authorities.
Speaking at the Centre for Investigative Journalism at City University last night, Mr Assange declared that the aggressive stance governments and corporations had taken against Wikileaks was proof that many are running scared of what the website can do.
"This is the smell of the fear that these organisations have of information coming out to the public."
Wikileaks goes to immense lengths to protect its sources by masking any leaks to its website through a series of routers around the world. Over the past three years, the website has carved itself a niche as one of the most extensive and safest platforms for whistleblowers to leak to, bypassing mainstream media by getting previously hidden information straight into the public domain.
It has broken reams of stories but few have created as many shockwaves as the Apache video, which gave the public an insight into how the US army's official narrative of the Baghdad attack differed from the truth. The website has never publicly confirmed whether Pfc Manning did leak the video.
The video footage shows two pilots firing amour-piercing, high-explosive rounds at a group of Iraqis which included two Reuters photojournalists. When a van pulls up to help the injured it is also attacked, killing the remaining people on the ground and injuring two children.
But Pfc Manning's arrest, Mr Assange said, was evidence that the US military was determined to undermine the site by going after its sources. He showed a secret memo by the US army detailing how Wikileaks was becoming a problem for the military.
"This [memo] speaks about how to deal with the problem. How to deal with us is to destroy out centre of gravity: the trust our sources have. And they recommend that by publicly prosecuting [them]."
Pfc Manning himself was exposed through a journalist, Adrian Lamo – who was once charged for hacking into The New York Times, Yahoo! News and Microsoft – and had been chatting with Pfc Manning over the internet following the April release of the video. The intelligence analyst allegedly boasted that he had been the original source of the footage and had also handed Wikileaks more than 260,000 classified documents from US embassies in the Middle East. Mr Lamo reported Pfc Manning to the FBI, defending his actions by saying he felt compelled to alert the authorities, and that he was not acting as a journalist when he spoke to Mr Manning.
The potential existence of thousands of diplomatic cables has caused immense concern to State Department officials. Mr Assange has said he is unaware of the cables but his lawyers have advised him against travelling to the US, fearing that he is now a potential suspect in the investigation into Pfc Manning.
Mr Assange said that, so far, US officials have made no attempts to contact him directly.
Asked whether he was concerned that Wikileaks' increasingly successful scoops on the US military may awaken what could become a formidable enemy, Mr Assange remained confident: "I think we'll be OK. I think the US recognises that it has to play by the rule of law."
Wikileaks' breaking stories...
*August 2007 – WikiLeaks unveils its first major scoop by exposing breath-taking levels of corruption by the family of the former Kenyan leader Daniel arap Moi. Julian Assange and activists in Kenya had got hold of a confidential report looking into the finances of Mr Moi's family. The scoop made headlines around the world.
*November 2007 – A copy of the Standard Operating Procedures for Camp Delta is posted online. The report, which was meant for US military eyes only, reveals that America has been keeping some prisoners at Guantanamo out of reach of the Red Cross.
*September 2008 – At the height of the 2008 presidential elections, the personal Yahoo email of Sarah Palin is hacked by David Kernell, a 20-year-old economics student. Many of the emails are leaked to WikiLeaks. Kernell was discovered in a police investigation, not through WikiLeaks.
*November 2008 – A full and unedited list of the membership of the British National Party appears briefly on a blog and permanently on WikiLeaks. The BNP leader Nick Griffin accuses disgruntled former members of being behind the leak. The list reveals that teachers, police officers and at least four religious ministers are members of the far-right party.
*July 2009 – WikiLeaks publishes a secret document from the Icelandic bank Kaupthing which reveals suspiciously large loans that were granted and written off just before the island's banking system collapsed. The report suggested that key players knew a financial meltdown was on the way and moved to protect their assets.
...and the next big leak?
*Garani Massacre. Julian Assange claims that Wikileaks is in possession of a detailed video of an airstrike which took place on the Afghan village of Garani last year. The website hopes to release the video by the end of the summer in a move that could cause renewed discomfort for the US military.
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