Bradley Manning, the American soldier who is accused of giving hundreds of thousands of secret documents to Wikileaks, may face a full court martial and life imprisonment.

If convicted of aiding the enemy - the most serious of the 36 charges brought against him - Manning, 24, could face a lifetime behind bars; he could technically have faced the death penalty, but a judge has already confirmed that this will not happen.

Manning was arrested in Iraq in May 2010 where he was accused of leaking hundreds of thousands of secret military documents - which he had access to through his role as an intelligence analyst in Baghdad - to Wikileaks, which then published the confidential documents online.

Julian Assange, creator of the whistle-blowing website, may also face charges as he presumably knew that he was dealing with stolen information which, in the wrong hands, could pose a threat to national security.

In December 2011 the military hearing was told that contact information for Assange was found on a computer hard drive belonging to Manning.

The leak, which is the largest breach of classified information in US history, is claimed to have already endangered American lives. Perry Nesmith, a former member of the Navy, told American news channel ABC: "We don't know how many people may have gotten killed or gotten hurt because of what he [Manning] has done."

Nesmith's comments come after reports that an enormous billboard with a photo of Manning and the words "Free Bradley Manning" being displayed close to the Army court at Fort Meade, where Manning is being questioned; the location is strategic because military decision-makers drive past the billboard every day.

Zack Pesavento, who helped organise the $16,000-per-month billboard, also spoke to ABC news: "Bradley Manning has always stayed true to his oath to defend the constitution. Manning has been subjected to all kinds of unconscionable abuse, prolonged solitary confinement and forced nudity, a lot of things that I don't think any American should be treated that way."

The US military released a statement, as reported by the Telegraph: "The investigating officer concluded that the charges and specifications are in the proper form and that reasonable grounds exist to believe that the accused committed the offenses alleged. He recommended that the charges be referred to a general court martial."

As of January 13, Manning has been, according to Wikileaks, in jail without charge for 599 days; the website tweets on its Twitter account almost daily how long Manning and Assange have both been detained without charge, along with how many days a banking blockade against Wikileaks has been in place - this now stands at 405 days.

On February 1 Assange will face the Supreme Court in London over allegations of rape and sexual assault of two Wikileaks volunteers, which could see him being extradited to Sweden - where the claims were made - to face questioning.