The British Home Secretary, Mr David Blunkett, yesterday reacted with dismay to a "deeply disturbing" High Court ruling which could result in the release of hundreds of asylum seekers from a new fast-track immigration centre.
A senior judge held that four Iraqi Kurds, who now plan to seek thousands of pounds in compensation, had been unlawfully detained at Oakington in Cambridgeshire so that their asylum claims could be processed more rapidly and efficiently.
The government fears that, unless the landmark decision is overturned on appeal, it could affect the attempt to operate "tough but fair" immigration controls.
The £4.5 million showpiece centre at Oakington opened in March last year.
A former RAF barracks, it has accommodation in the former officers' mess for mothers and children and separate dormitory blocks for men.
Detainees are given access to independent legal advice provided by refugee law groups and interviewed by immigration officers.
Ministers hoped it would play a major role in reducing the backlog of more than 100,000 undecided asylum applications.
Latest British Home Office figures show the centre has dealt with 8,916 applicants, plus 2,239 dependants such as spouses and children.
Today its current operation was dealt a serious blow when Mr Justice Collins, sitting in London, held that to impose detention just to speed up the determination of claims, when there was no threat of asylum seekers absconding and attempting to enter the country illegally, breached human rights laws.
The judge gave the government permission to launch an urgent appeal, saying it was "obviously a matter of very considerable public importance".
In order to prevent a flood of legal claims from other Oakington detainees, the judge suspended making a formal declaration on the law pending the appeal hearing.
The Iraqi Kurds' solicitor, Mr Michael Hanley, said: "My clients felt they were in prison in Oakington. They will be pleased that other asylum seekers will hopefully not be subjected to the same treatment." He estimated the amount of damages for unlawful detention which would be claimed by his clients at a High Court hearing due in November, if the government appeal fails, at between £5,000 and £10,000 per person.
A Home Office spokesman said Mr Blunkett was "deeply disturbed" by the ruling and the government aimed to go to the Court of Appeal by October 5th.
His lawyers argued that Oakington, near Cambridge, was a reception centre rather than a detention facility and its operation completely lawful.
Pending the appeal, current operations will continue as normal at the centre, where asylum seekers are held for up to seven days, and sometimes longer, with no access to bail to ensure the rapid processing of their refugee claims.
A Home Office spokesman said: "The Home Secretary is deeply disturbed at the implications of the judgment for the effective operation of tough but fair immigration controls".
But campaigners for the rights of asylum seekers described the ruling as "a credit to British justice" and predicted that hundreds more refugees would bring claims.