A SCOT hacked into the US military computer system, paralysing a naval base soon after the September 11 attacks, a court was told yesterday.

Counsel for the US government claimed Gary McKinnon, 39, left a note on an army computer, saying US foreign policy was akin to government-sponsored terrorism.

The note added: "It was not a mistake that there was a huge security stand down on September 11th last year . . . I am SOLO. I will continue to disrupt at the highest levels."

The allegations were made during the opening of Mr McKinnon's extradition hearing at Bow Street Magistrates' Court.

The Glasgow-born defendant faces extradition to the US over claims he accessed 97 government computers over a one-year period, causing £370,000 worth of damage.

One allegation relates to Mr McKinnon deleting operating system files and logs from computers at US Naval Weapons Station Earle at a critical time after the September 11 attacks, rendering the base's entire network of more than 300 computers inoperable. His goal was to gain access to the US military classified information network, the court heard.

Mr McKinnon, of Wood Green, north London, is contesting the extradition request.

Mark Summers, for the US government, told the court Mr McKinnon was acting from his own computer in London.

He said: "Via the internet, the defendant identified US government network computers with an open Microsoft Windows connection."

Mr McKinnon is also accused of deleting files which shut down the entire US army's military district of Washington's network of more than 2000 computers for 24 hours, "significantly disrupting governmental function".

Mr Summers said: "The defendant's conduct was intentional and calculated to influence and affect the US government by intimidation and coercion."

Mr McKinnon is accused of 20 counts relating to the US Army, US Navy, Nasa, the Department of Defence and the US Air Force. These include accessing computers, intending to steal computer files and data, and stealing computer files from the army, navy and Nasa.

It is also alleged he obtained secret passwords or information which might become "indirectly useful to an enemy" from the army, navy and Nasa, as well as interfering with maritime navigation facilities in New Jersey in relation to the navy.

Mr McKinnon spoke only to confirm his name during the hearing, which was adjourned until October 18. He was granted bail subject to restrictions, including a ban on using any computer equipment allowing him to access the internet.

Outside the court, Karen Todner, his solicitor, said Mr McKinnon faced a maximum sentence of 70 years if found guilty in the US, adding: "Gary McKinnon continues to vigorously contest his extradition.

"The public need to ask why British citizens are being extradited to the USA when the US government has not signed the extradition treaty between the two countries."