LONDON - The first prisoner to be released from Guantanamo Bay in Cuba, since US President Barack Obama ordered a review of all detainee cases, arrived in Britain Monday alleging that he was subjected to ‘medieval’ torture in which British intelligence services had been complicit.

Binyam Mohamed, a 30-year-old Ethiopian national who lived in Britain before his arrest in Pakistan in 2002, touched down at a military airport near London, accompanied by a doctor and government officials.

He was detained by immigration officials for several hours of questioning but released Monday evening, London’s Metropolitan Police said.

The ex-prisoner was hoping to be reunited with his family and friends in a ‘quiet place’, his lawyers said.

Before touching down at a Royal Air Force (RAF) base near London Monday, Mohamed repeated his allegation that the ‘people who were torturing me were receiving questions and materials from British intelligence’.

In a statement released through his lawyers, he said he had experienced his ‘darkest nightmares’.

‘It is still difficult for me to believe that I was abducted, hauled from one country to the next, and tortured in medieval ways - all orchestrated by the US government,’ said Mohamed.

The British government, which has repeatedly denied allegations of collusion in the alleged ill-treatment, welcomed Mohamed’s release.

‘We very much welcome President Obama’s commitment to close Guantanamo Bay and I see today’s return of Binyam Mohamed as the first step towards that shared goal,’ Foreign Secretary David Miliband said.

Prime Minister Gordon Brown declined to be drawn on the question of whether Mohamed, who came as a refugee to Britain in 1994, would face any restrictions on his liberty.

‘My first concern is the security of people in this country and we will do everything in our power to protect the security of people in our country,’ he said.

Asked whether he would support the publication of secret US documents, which Mohamed’s legal team believe would prove that he was tortured, Brown said it was important to maintain the confidential nature of intelligence exchanges.

‘If there is no confidence between the security services of two countries that cooperate very much with each other, then it is very difficult for there to be the exchange of information that is necessary,’ he said.

US Attorney General Eric Holder released a statement in Washington thanking the British government for its efforts in having the detainee transferred and urged other countries to play a role in helping the new administration close the camp.

‘The friendship and assistance of the international community is vitally important as we work to close Guantanamo,’ said Holder, who embarked on a visit to the prison facility Monday to review detention and interrogation policies.

Mohamed’s sister, Zuhra, said in London that she was ‘thankful for everything that was done for Binyam to make this day come true’.

Meanwhile, Amnesty International called for an independent inquiry into Britain’s role in ’secret detention and rendition programmes’.

Mohamed was arrested in Pakistan in April 2002, and later flown to Morocco before being moved to Afghanistan. He was transferred to Guantanamo in 2004.

He alleges that British agents colluded in his torture during ‘rendition’ to Morocco between 2002 and 2004.

Speaking of his alleged torture in Morocco, Mohamed said: ‘I have met British intelligence in Pakistan. I had been open with them. Yet, the very people who I had hoped would come to my rescue, I later realised, had allied themselves with my abusers.’

‘I am not asking for vengeance; only that the truth should be made known so that nobody in the future should have to endure what I have endured,’ the statement said.

Mohamed’s lawyer, Clive Stafford Smith, said he was ‘absolutely convinced’ of his client’s innocence. ‘He is a victim who has suffered more than any human being should ever suffer,’ said Stafford Smith.

Lawyers are expected to press for the release of secret CIA documents supplied to the High Court in London which, they allege, would prove the ill-treatment of their client.

Earlier this month, two senior judges said they were told by the British government not to release the documents in order not to jeopardise intelligence cooperation between Britain and the US.

US charges of his involvement in a plot to stage a ‘dirty bomb’ on the US were dropped by the military authorities in Guantanamo last October.