In February 2010, the UK Court of Appeal ruled that he had been subjected to "cruel, inhuman and degrading treatment by the United States authorities"[5] in which the British Intelligence services had been complicit.

On 10 April 2002, Mohamed was arrested at Pakistan's Karachi airport by Pakistani authorities as a suspected terrorist, while attempting to return to the UK under a false passport.

[8] Mohamed contends that he was subjected to extraordinary rendition by the United States, and entered a "ghost prison system" run by US intelligence agents[9] in Pakistan, Morocco[10] and Afghanistan.

[11] On 19 September 2004, Mohamed was taken by U.S. military authorities from Bagram airbase in Afghanistan to their Guantánamo Bay detention camp at their Navy base in Cuba.

From a written statement by Mohamed dated 11 August 2005: The administration promised that if we gave them 10 days, they would bring the prison into compliance with the Geneva conventions.

The complaint alleges that Mohamed was trained in Kabul to build dirty bombs (weapons combining conventional explosives with radioactive material intended to be dispersed over a large area).

According to the complaint, he "was planning terror attacks against high-rise apartment buildings in the United States and was arrested at an airport in Pakistan, attempting to go to London while using a forged passport.

[19][20] Carol J. Williams, writing in the Los Angeles Times, reported that all five men had been connected to Abu Zubaydah—one of the three captives the CIA has acknowledged was interrogated using the controversial technique known as waterboarding.

[11][23] On 21 June 2008, The New York Times reported that the UK Government had sent a letter to Clive Stafford Smith, confirming that it had information about Mohamed's allegations of abuse.

[29] The reasons given were that—even if it was unreasonable for it to affect international relations—if the Foreign Secretary thought it was going to harm the special intelligence relationship with the United States, it would not be in the public interest.

According to the CBC report, Canada had an obligation to object if it determined that the Americans had falsely represented US security officials as Canadians, as a ploy to trick Mohamed into confessing.

On 7 August 2007, the British Foreign Secretary David Miliband requested that the US release Mohamed and four other Guantánamo detainees, all of whom had been granted refugee status or other legal right to remain in the United Kingdom, prior to their capture by US forces.

[40] The Independent quoted a recently declassified note from Mohamed: "It has come to my attention through several reliable sources that my release from Guantánamo to the UK had been ordered several weeks ago.

While the claims of MI5 collusion were being investigated by the British government, the Shadow Justice Secretary, Dominic Grieve, called for a judicial inquiry into the allegations and for the matter to be referred to the police.

On 12 March 2009, in an op-ed piece in The Guardian, the analyst Timothy Garton Ash called for Mohamed's claims of torture and MI5 collusion to be referred to the Director of Public Prosecutions.

Despite attempts by the Foreign Secretary, David Miliband, to suppress evidence on the grounds that such disclosure would harm national security, the government lost the case in the High Court.

In an unprecedented case, counsel for The Guardian and other media organisations, Mohamed and two civil rights groups, Liberty and Justice, argued that the public interest in disclosing the role played by British and US agencies in unlawful activities far outweighed any claim about potential threats to national security.

[47][48] On 20 December, a U.S. District Court judge, Gladys Kessler, found that there was "credible" evidence that a British resident was tortured while being detained on behalf of the US Government.

Her formerly classified legal opinion, obtained by The Observer, records that the US Government does not dispute "credible" evidence that Binyam Mohamed had been tortured while being held at its behest.

[49][50] On 27 January 2010, The Guardian reported that "United Nations human rights investigators had concluded that the British government had been complicit in the mistreatment and possible torture of several of its own citizens during the 'war on terror'".

[51] On 10 February, three Court of Appeal judges ordered the British government to reveal evidence of MI5 and MI6 complicity in the torture of Binyam Mohamed, overruling the Foreign Secretary, David Miliband.

According to The Guardian, an anonymous White House official told them: "the court decision would not provoke a broad review of intelligence liaison between Britain and the US because the need for close co-operation was greater now than ever.