An inquiry into MI5’s alleged complicity in the detention without trial at Guantanamo Bay of two British residents is believed to have concluded that the intelligence service made serious mistakes, The Times has learnt.

The parliamentary Intelligence and Security Committee (ISC) has been investigating the detention of Bisher al-Rawi and Jamil el-Banna by the CIA and their transfer by “ghost flight” to the American internment camp in Cuba.

The ISC’s report was due on the Prime Minister’s desk later this month but has been delayed after the release last weekend of Mr al-Rawi.

Crucial to the inquiry are documents that show that MI5 had approached both men to become informants because of their acquaintance with a radical Islamist cleric.

The papers, released under American freedom of information legislation, appear to show that Mr el-Banna refused offers of money and a new identity while Mr al-Rawi tried to pull out of an unpaid arrangement with MI5 agents. Later British agents sent telegrams to the CIA, alerting it to the men’s arrival in The Gambia from London on a business trip.

The telegrams described the men as Islamists and extremists who were close to Abu Qatada, a key figure in the al-Qaeda movement in Europe, now in prison in Britain.

Both men were arrested in The Gambia and transferred first to Bagram airbase, Afghanistan and then to Guantanamo Bay. They were flown on unmarked CIA flights and are among the few Britons to have been subjected to extraordinary rendition — the transfer of detainees across borders without recourse to any legal process. Sources have told The Timesthat the preliminary judgment of the ISC is that MI5 made “operational” mistakes but that it did not know that the two men would be subject to rendition and internment at Guantanamo Bay.

Mr al-Rawi, 39, spoke of the “nightmare” he had endured at the US camp and appealed to the Government to work for the release of Mr el-Banna, 43.

Both men admit knowing Abu Qatada but deny involvement in extremist activity. Neither has been charged with any terror offence in Britain.

Reprieve, the legal campaign group, says that another eight men with the right to live in Britain are among the estimated 430 still being held at the camp.

But the Foreign and Commonwealth Office, which negotiated the return of Mr al-Rawi, said it had not asked the US to release any of the other detainees with British links.

A spokesman said: “They are all foreign nationals and therefore we have no locus to provide diplomatic or consular assistance to them.

“The facts of Mr al-Rawi’s case are different and the Foreign Secretary took a decision to ask the Americans to release him back to the UK.”

Clive Stafford Smith, of Reprieve, said, however, that he believed Mr al-Rawi’s release was a breakthrough.

“If Bisher can be freed so too can Jamil el-Banna. Their cases are identical,” he said.

“The British Government holds the key — if they would just say the word he would be home. The Americans are desperate to release people and close Guantanamo down.

“The problem is the Home Office. They spend their whole time trying to deport people, they don’t want them coming into the UK.”

The rendition

Jamil el-Banna, a father of five, described his arrest to a military tribunal at Guantanamo Bay. This is an extract from the transcript:

Jamil el-Banna: They took me, covered me, put me in a vehicle and sent me somewhere — I don’t know where. It was at night. Then from there to the airport right away.

Tribunal: An airport in Gambia?

El-Banna: We were in a room with about eight men. All with covered-up faces.

Tribunal: Were you by yourself?

El-Banna: Yes. They cut off my clothes. They were pulling on my hands and my legs. They put me in an airplane and they made me wear the handcuffs that go around your body so I would not do anything on the airplane . . .

Tribunal: Is this the time you said you were kidnapped?

El-Banna: This is all kidnapping. Yes. They took me underground in the dark. I did not see light for two weeks.

Tribunal: Is that after you travelled to Afghanistan or Pakistan?

El-Banna: After I got off the airplane.

Tribunal: In where?

El-Banna: Bagram, Afghanistan . . . I did not know what I did wrong or what I did.

Source: US military

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