LONDON - A British computer hacker has won his 10-year fight against extradition to the U.S. with the U.K. government saying he was unfit to face the charges against him.

In a statement to the House of Commons on Tuesday, Britain’s Home Secretary Theresa May said that the extradition of Gary McKinnon, a 46-year-old computer administrator from London, "would give rise to such a high risk of him ending his life that extradition would be incompatible with Mr. McKinnon’s human rights.”

“There is no doubt that Mr. McKinnon is accused of serious crimes, but there is also no doubt he is seriously ill," she said.

McKinnon, who suffers from Asperger’s syndrome – a high-functioning form of autism – admits hacking into U.S. military computers, but claims he was looking for evidence of extraterrestrial life. Warrants for his arrest were issued in New Jersey and Virginia in late 2002, amid allegations by U.S. officials that  the former computer systems administrator accessed 97 military and NASA computers between 2001 and 2002, disabling key naval systems and causing more than $700,000 of damage. 

One U.S. prosecutor called his activities “the biggest military computer hack of all time.”

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Gary McKinnon won a 10-year fight on Tuesday against extradition to the U.S. He is seen here making his way into a London courthouse in July 2005.

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Legal proceedings to have McKinnon extradited to the U.S. stepped up a gear in 2005, when he was re-arrested by officers from Scotland Yard’s extradition unit at his home in north London. What followed was a saga of appeals, reviews and adjournments, centering on McKinnon’s mental health and the fairness of the extradition request. This culminated in a decision in May 2010 by the Home Secretary that the case should be adjourned while further medical evidence was considered.

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British Home Secretary Theresa May, seen here leaving a meeting at 10 Downing Street, announced on Tuesday that accused British computer hacker Gary McKinnon will not be extradited to the United States after a 10-year battle.

Two independent psychological reviews suggested that McKinnon was likely to commit suicide if he was extradited.

It is now up to British prosecutors to decide whether McKinnon must face charges in Britain, May added. 

His mother, Janis Sharp, said on the eve of Tuesday’s announcement, that the ups and downs of the legal process have been so cruel they amount to "waterboarding of the mind.”

Among the diplomatic maneuvering the case provoked were discussions between Prime Minister David Cameron and President Barack Obama. Leaked documents also revealed how Cameron’s predecessor, Gordon Brown, had unsuccessfully proposed a deal to allow McKinnon to serve any prison sentence in a British jail.

McKinnon’s supporters say he acted through "naivety" as a result of his condition, and should not be considered a criminal.

U.K. hacker's latest U.S. extradition appeal fails

"Gary is a classic computer nerd, he was looking for UFOs, that was what he was searching for," McKinnon's lawyer Karen Todner told BBC Radio on Tuesday morning.

McKinnon was 14-years-old when he started developing computer software on his home computer. He started hacking after watching the 1983 movie War Games, in which a teenager brings the world to the brink of war by hacking into the Pentagon computer network.

ITV News contributed to this report.

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AP, file

Abu Qatada makes a televised appeal from high security prison in London calling for the release of British hostage Norman Kember in Iraq in a picture released in 2005.

An extremist cleric described as one of Europe's leading al-Qaida operatives should not be deported to Jordan to face trial because of the risk that evidence obtained through torture would be used against him, Europe's highest court ruled Tuesday.

After a six-year legal battle, the European Court of Human Rights ruled that deporting Abu Qatada from Britain — where he is in prison custody — would "give rise to a flagrant denial of justice."

The move means that within days Qatada could apply for bail to be released from the maximum security prison where he is being kept, the Guardian newspaper reported.

Abu Qatada — whose real name is Omar Mahmoud Mohammed Othman — is an extremist Muslim preacher from Jordan who has been described by European courts as a leading al-Qaida figure in Europe.

A Palestinian-Jordanian citizen, Abu Qatada arrived in Britain in 1993 and was detained in 2002 under anti-terrorism laws which at the time allowed suspected terrorists to be held in jail without charge.

Though Abu Qatada was released in 2005, when the unpopular law was overturned, he was kept under surveillance and arrested again within months, to be held pending his deportation to face terrorism charges in Jordan.

While living in Britain, he was convicted in his absence in Jordan of terrorist offenses related to two alleged bomb plots.

Never faced UK charges
Although Abu Qatada has never faced criminal charges in Britain, authorities in the U.K. have accused him of advising militants and raising money for terrorist attacks. He "is a leading spiritual advisor with extensive links to, and influence over, extreme Islamists in the U.K. and overseas," prosecutors told a British court in 2007.

Britain's Home Secretary Theresa May said the U.K. would consider appealing the European court's decision. It has a three-month window in which to make any appeal, the court said.

"I am disappointed that the court has made this ruling," May said in a statement. "This is not the end of the road, and we will now consider all the legal options available to us."

Abu Qatada will remain held in British prison custody while a decision is made, she said.

May has not specified what Britain would do if it loses any appeal, though it is likely Abu Qatada would be freed from prison and monitored under a surveillance program which requires those suspected of involvement in terorrism — but not charged with any crime — to abide by a curfew and wear an electronic anklet.

Britain's Special Immigration Appeals Commission has previously been told Abu Qatada was also suspected of links to a bomb plot in Strasbourg, France, and to the raising of funds for terrorism in Chechnya.

In their ruling, the European judges based in Strasbourg said they did not accept Abu Qatada's claims that he would face ill treatment or torture at the hands of Jordanian authorities if sent there for trial, citing recent agreements between Jordan and the U.K.

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But the judges warned that evidence in his case had been obtained by torturing his co-accused.

"The court found that torture was widespread in Jordan, as was the use of torture evidence by the Jordanian courts," the ruling said. "In relation to each of the two terrorist conspiracies ... the evidence of his involvement had been obtained by torturing one of his co-defendants."

Judges said evidence obtained through torture was illegal under international law and was also unreliable. The ruling said "there was a high probability that the incriminating evidence would be admitted ... and that it would be of considerable, perhaps decisive, importance."

Britain's highest court had ruled in 2009 that Abu Qatada should be deported to Jordan, despite fears over his potential mistreatment.

Human rights group Liberty urged the British government to make efforts to have Abu Qatada prosecuted in Britain.

"The case ... constitutes a damning indictment of the Jordanian criminal justice system where torture and evidence obtained by torture are completely commonplace," Shami Chakrabarti, the group's director, said in a statement. "So it is clear that, if Abu Qatada is to be tried for terrorism, this should happen in a British court without further delay."

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The Associated Press and msnbc.com staff contributed to this report.