LONDON, March 18: Britain's Appeal Court ordered the government to free a Libyan terror suspect on Thursday, upholding the first defeat of emergency, post-September 11 powers to hold foreigners without charge.

The man, known only as M, had been held without charge for two years at London's high security Belmarsh prison. But Lord Chief Justice Lord Woolf upheld a decision by a highly secretive special tribunal that the authorities had no 'reasonable grounds' to suspect he had links to terrorism, and he should therefore go free.

The ruling came as a surprise to rights groups, who had said the government's emergency anti-terror powers were so draconian they believed none of the suspects would ever be released.

Defence lawyer Gareth Peirce said she hoped M would be "free tonight and back with his family". "It is our belief, as we have stated throughout, that the system is profoundly unfair and that it was intended nobody would get out," she said. "These detainees feel they are forgotten men."

A Home Office spokeswoman said the government's defeat proved "that the system works". "We intentionally created a robust system to provide legal scrutiny of the certifications made by the home secretary. We gave the courts the power to overturn the decision," she said.

She declined to comment on when or whether the authorities would now allow M to go free. Under the powers, enacted after the September 11, 2001 attacks on the United States and Washington, British authorities can jail foreign suspects indefinitely without charge.

The authorities must show only that they have "reasonable grounds to suspect" the detainees have links to terror, a standard far below the "proof beyond a reasonable doubt" needed to convict them of an actual crime.

Authorities can also present secret evidence to the tribunal, the Special Immigration Appeals Commission (SIAC) without the suspects or their lawyers present.

But the SIAC ruled last week that even under those rules, the government's case against M was "not reliable and that reasonable suspicion is not established".

The Home Office asked Lord Woolf's permission to appeal, but in Thursday's ruling he declared the case closed. "It has not been shown that this decision was one to which SIAC was not entitled to come to because of the evidence, or that it was perverse, or that there was any failure to take into account any relevant consideration," Lord Woolf said.

Britain has 13 other foreigners in jail under the emergency powers, which are due to be renewed and have been strongly criticized by a cross-party parliamentary committee. -Reuters