Gordon Brown was under growing pressure to hold an independent inquiry into Britain’s complicity in torture last night after ministers admitted that terror suspects detained by British soldiers in Iraq were secretly flown by the US to Afghanistan.

John Hutton, the Defence Secretary, told MPs that despite repeated official assurances to the contrary, British soldiers were involved in at least one case of rendition. Two suspects captured and detained by British Special Forces outside Baghdad in 2004 were subsequently removed by the US to Afghanistan where they remain in detention. There was “no evidence” that the two, believed to be Pakistani members of Lashkar-e-Taiba, a proscribed organisation with links to al-Qaeda, had been tortured, Mr Hutton insisted.

But the Government’s embarrassment was heightened when Mr Hutton revealed that officials told Jack Straw and Charles Clarke about the case in April 2006 in internal briefing papers. Mr Straw repeatedly denied that Britain was involved in rendition while he was Foreign Secretary. Yesterday Mr Hutton sought to defend his colleagues, saying that officials had made only “brief references” to the case in “lengthy papers” which did not “highlight its significance”. However, he added: “It is clear to me that the transfer to Afghanistan of these two individuals should have been questioned at the time.”

A spokesman for Mr Straw said: “If he had been alerted to the significance of the case at the time it’s a fair suggestion that he would have brought it to the attention of Parliament.”

The admission is the latest in a series of revelations that campaigners say undermine official denials that Britain systematically helped to facilitate the sending of suspects for US interrogation to countries where torture is not illegal.

Allegations that MI5 officers were complicit in the torture of the British resident Binyam Mohamed in Morocco are being investigated by the Attorney-General. David Miliband, the Foreign Secretary, admitted last year that, despite previous denials, the British territory of Diego Garcia was used in the US rendition of suspected terrorists.

Mr Hutton made the latest admission after allegations by a former SAS officer, Ben Griffin, that British soldiers routinely turned over captives to US forces in the knowledge that they would be tortured.

The Defence Secretary said that while a review by a senior general had found no evidence to substantiate the claims of complicity in torture, it had revealed at least one case of British involvement in rendition. He also apologised for inaccuracies in figures on the number of detainees held by British Forces in the period since January 2004. He said that in three parliamentary answers since February 2007, ministers overstated by about 1,000 the number of detainees held.

Andrew Tyrie, chairman of the All-Party Parliamentary Group on Extraordinary Rendition, called for a full Government inquiry into British involvement in the US rendition programme. He said US assurances that it did not use torture were unreliable.

The two suspected Lashkar-e-Taiba terrorists were detained in a nighttime raid by special forces, according to defence sources, and were described yesterday by military officials as “very, very bad people”. The SAS, backed by soldiers from the Special Forces Support Group, had been engaged since 2003 in one of the most challenging covert counter-terrorist operations in the regiment’s history. They were working alongside Delta Force and other US special forces units.

The SAS had no facilities for holding prisoners and handed them to the Americans for interrogation. This was normal procedure, although never publicly acknowledged. Military sources said the Americans did not have interpreters to help in the interrogation of the two men, which was why they were shipped out of Iraq and sent to the US base at Bagram in Afghanistan to be questioned.

The review by the general uncovered a confused paper trail. According to American records, US special forces had arrested the two suspects, but it was clear from the paperwork provided by the SAS at Hereford that it had been a British operation.

What is still not clear is why the Ministry of Defence was not included when the reference to the handover of two prisoners to the Americans in 2004 was circulated in a briefing note to ministers at the Home Office and Foreign Office in 2006.

The unanswered questions

Q Who were the two people whose rendition flights refuelled at Diego Garcia in 2002, where were they held and how were they treated?

Q Were agreements for the use of Diego Garcia breached and were any crimes committed by British or US personnel? Q Was Diego Garcia involved in other cases, as has been alleged?

Q How exactly was Binyam Mohamed treated and what did MI5 know of his treatment?

Q Is there truth in the allegations made by Ben Griffin, an ex-SAS officer, that prisoners captured by British forces in Iraq were handed to US forces in the knowledge that they would be tortured?

Q Were the two detainees the MoD confirms to have been rendered from Iraq to Afghanistan treated in accordance with Britain’s legal obligations?

Official denials

Unless we all start to believe in conspiracy theories and that the officials are lying, that I am lying, that behind this there is some kind of secret state which is in league with some dark forces in the United States, and also let me say, we believe that Secretary Rice is lying, there simply is no truth in the claims that the United Kingdom has been involved in rendition
Jack Straw, then Foreign Secretary, December 13 2005 (evidence to Foreign Affairs Committee)

We are unaware of any individuals originally detained by UK authorities and subsequently rendited by the USA
Kim Howells, December 2005 (response to parliamentary question)

As recently as September we have had robust assurances from the US that at no time have there been any detainees either on Diego Garcia or transiting through the UK’s territorial seas or air-space surrounding Diego Garcia
Kim Howells, then Foreign Office Minister, November 2007 (letter to Andrew Tyrie, MP)

Whenever we have passed an individual from UK jurisdiction into the jurisdiction of the Iraqi, Afghan or US authorities, we have had in place an understanding that they would not transfer that individual to a third country without first seeking our consent or at least informing us of their intention
Ministry of Defence, January 31, 2008 (correspondence)

To end all speculation would require us to prove a negative. We can say, however, that we have no evidence of unlawful rendition and we have looked
Ministry of Defence, July 2008 (from review into detention)

I remain confident that the processes currently in place are in accordance with UK policy and legal obligations
John Hutton, Defence Secretary, January 13, 2009 (correspondence with All-Party Parliamentary Group)

We were not complicit in any cases where it was advocated and implied that someone would be subject to mistreatment
Security Service, as reported July 2007 (giving oral evidence to Intelligence Committee)

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