The Home Secretary has released a man regarded as one of Britain’s most dangerous terror suspects from virtual house arrest to avoid disclosing secret evidence against him, The Times has learnt.

The man, known only as AF, has been subject to a controversial “control order” since 2006 because of his alleged links with Islamic terrorists. He has never been charged, however, and the evidence for the allegations has never been heard in a public court.

The control order was revoked last week and the suspect’s electronic tag removed, setting him free in spite of the Government’s claim that he remains a threat.

Lord Pannick, QC, who led the legal team acting for the man in the House of Lords, said: “The Home Secretary has some explaining to do. Does he now accept that there was no need for the control order which imposed severe restrictions on AF . . . or does he still think there is a need for controls but is unwilling to provide details of the allegations against AF? If the latter, does he accept that the control order regime is defective and should be scrapped?”

AF, who has dual Libyan and British nationality, was one of three terror suspects who won a landmark ruling from nine law lords in July that their detention under the control order regime was illegal. The law lords ruled that the suspects had been denied a fair hearing prior to detention because they had not been told sufficient details of the case against them.

The ruling paved the way for up to 20 men held under the regime to challenge their detention and to seek to know the basis of the case against them.

Alan Johnson, the Home Secretary, said at the time that the Government would contest each case vigorously. Ministers were faced with either disclosing secret intelligence-based evidence — with the risk, as they see it, of jeopardising intelligence sources or methods — or of releasing the men.

However, in a letter sent at the end of last month to the man’s solicitor, the Home Secretary said that he was revoking the control order under which AF had been held for three years. No reason was given.

AF, who was born in 1981 in Derby to a Libyan father and English mother, lives in a flat on the outskirts of Manchester. He was confined for up to 16 hours a day.

Carl Richmond, solicitor with the law firm Middleweeks who acts for AF, said that the legal team would now seek to have the control order formally quashed in the High Court at a hearing in late October or early November. “He feels numb about it all, almost disbelief,” Mr Richmond said. “The letter came out of the blue, with no warning.”

He added: “The control order was revoked last week. He has had his electronic tag removed and is just coming to terms with trying to readjust to a normal life.

“AF has always insisted that he has done nothing wrong. Clearly any evidence was such that the Home Secretary felt unable to disclose it. But we would argue that it was not material and could not have been relied upon in any case.”

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