London Britain’s intelligence agencies engaged in a series of previously-unknown joint operations with Colonel Muammar Gaddafi’s government, and used the information extracted from rendition victims as evidence during partially-secret court proceedings in London, according to an analysis of official documents recovered in Tripoli since the Libyan revolution.

The exhaustive study of the papers from the Libyan government archives shows the links between MI5, MI6 and Gaddafi’s security agencies to have been far more extensive and than previously thought, and to have involved a number of joint operations in which Libyan dissidents were unlawfully detained and allegedly tortured. At one point, Libyan intelligence agents were invited to operate on British soil, where they worked alongside MI5 and allegedly intimidated a number of opponents of Gaddafi who had been granted asylum in the UK.

Previously, MI6 was known to have assisted the dictatorship with the kidnap of two Libyan opposition leaders who were flown to Tripoli along with their families — including a six-year-old girl and a pregnant woman — in 2004. However, the study of the archives suggests the fruits of a series of joint UK-Libyan clandestine operations also underpinned a significant number of court hearings in London between 2002 and 2007, during which the last Labour government unsuccessfully sought to deport Gaddafi’s opponents on the basis of information extracted from people who had been “rendered” to his jails.

In addition, the documents show four men were subjected to control orders in the UK — a form of curfew — on the basis of information extracted from victims of rendition who had been handed over to the Gaddafi regime. The papers recovered from the dictatorship’s archives include secret correspondence from MI6, MI5 reports on Libyans living in the UK, a British intelligence assessment marked “UK/Libya Eyes Only — Secret”, and official Libyan minutes of meetings between the two countries’ intelligence agencies. They show that: UK intelligence agencies sent more than 1,600 questions to be put to the two opposition leaders, Sami Al Aadi and Abdul Hakim Belhaj, despite having reason to know they were being tortured.

British government allegedly lawyers drew upon the answers to those questions when seeking the deportation of Libyans living in the UK.

Five men were subjected to control orders in the UK, allegedly on the basis of information extracted from two rendition victims.

Gaddafi’s agents recorded MI5 as warning in September 2006 that the two country’s agencies should take steps to ensure that their joint operations would never be “discovered by lawyers or human rights organisations and the media”.

In fact, papers that detail the joint UK-Libyan rendition operations were discovered by the New York-based NGO Human Rights Watch, in September 2011, at the height of the Libyan revolution, in an abandoned government office building in Tripoli.

Since then, hundreds more documents have been discovered in government files in Tripoli. A team of London-based lawyers has assembled them into an archive that is forming the basis of a claim for damages on behalf of 12 men who were allegedly kidnapped, tortured, subject to control orders or tricked into travelling to Libya where they were detained and mistreated.

An attempt by government lawyers to have that claim stuck out was rejected by the high court in London on Thursday, with the judge, Justice Irwin, ruling that the allegations “are of real potential public concern” and should be heard and dealt with by the courts. The litigation follows earlier proceedings brought on behalf of the two families who were kidnapped in the far east and flown to Tripoli. One claim was settled when the government paid £2.23m (Dh12.28 million) in compensation to Al Saadi and his family; the second is ongoing, despite attempts by government lawyers to have it thrown out of court, with Belhaj suing not only the British government, but also Sir Mark Allen, former head of counter-terrorism at MI6, and Jack Straw, who was foreign secretary at the time of his kidnap. Belhaj has offered to settle for just GBP3, providing he and his wife also receive an unreserved apology. This is highly unlikely to happen, however, as the two rendition operations are also the subject of a three-year Scotland Yard investigation code-named Operation Lydd. Straw has been questioned by detectives: his spokesman says he was interviewed “as a witness”. Last month detectives passed a final file to the Crown Prosecution Service. No charges are imminent, however.

The CPS said: “The police investigation has lasted almost three years and has produced a large amount of material. These are complex allegations that will require careful consideration, but we will aim to complete our decision making as soon as is practicably possible.” The volte-face in UK-Libyan relations was always going to be contentious: the Gaddafi regime had not only helped to arm the IRA, bombed Pan Am Flight 103 over the Scottish town of Lockerbie with the loss of 270 lives in 1988, and harboured the man who murdered a London policewoman, Yvonne Fletcher, four years earlier; it had been responsible for the bombing of a French airliner and a Berlin nightclub, and for several decades had been sending assassins around the world to murder its opponents.

The Tripoli archives show that the rapprochement, which began with the restoration of diplomatic ties in 1999, gathered pace within weeks of the Al Qaida attacks of 9/11. Sir Richard Dearlove, who was head of MI6 at the time, said that these links were always authorised by government ministers.

The week after the attacks, British intelligence officers met with Moussa Koussa, the head of Libyan intelligence, who offered to provide intelligence from Islamists held in the regime’s jails.

Two months later British intelligence officers held a three-day conference with their Libyan counterparts at a hotel at a European airport. German and Austrian intelligence officers also attended. According to the Libyan minutes, the British explained that they could not arrest anyone in the UK — only the police could do that — and that there could be difficulty in obtaining authorisation for Gaddafi’s intelligence officers to operate in the UK. They also added that impending changes to UK law would give them “more leeway” in the near future.

— Guardian News & Media Ltd