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.

Facundo Arrizabalaga / EPA

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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