Gary McKinnon's mother has pleaded with President Obama to intervene after the 'UFO hacker' lost his legal fight against extradition to the US.

American authorities want to put the 43-year-old on trial for hacking into US military networks, including the Pentagon.

Mr McKinnon is accused of the "biggest military hack of all time", involving nearly 100 government computers belonging to organisations including the US Navy and Nasa.

His mother, Janis Sharp, said: "This is the Bush era, not the Obama era. Please hear us Obama."

She is appealing to the US President to use his powers to save her son from a potential 70 year jail term.

Mr McKinnon, who suffers from Asperger's Syndrome, admits hacking into computers in America during a period of heightened security in the wake of the September 11 2001 attacks, but claims he was looking for evidence of extra-terrestrial life.

His supporters fear his medical condition, coupled with the stress of extradition and tough American prison conditions, could result in psychosis and suicide.

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