The man accused of hacking 53 US government and space agency networks has been released on bail for £5,000.
Gary McKinnon, a 39 year-old unemployed man from north London, appeared on Wednesday at Bow Street Magistrates Court to face extradition charges by the US government.
According to Metropolitan Police, the extradition warrant says he gained illegal access and made unauthorised modifications to 53 computers belonging to the US government, including computers from the Department of Defense, Nasa (National Aeronautics and Space Administration) and the National Security Agency, between February 2001 and March 2002.
He was arrested by officers from the Metropolitan Police Service Extradition Unit on Tuesday night.
The US government said Mckinnon's hacking caused downtime and personnel costs of around $1m (£0.6m).
If extradited and found guilty in the US, he faces five years in prison for eight crimes he was indicted for in 2002. Among the charges, McKinnon is suspected of stealing administrator identities, deleting 1,300 user accounts and copying a file containing usernames and encrypted passwords.
McKinnon, known as 'Solo' in the hacking world, was granted bail until the next hearing on 27 July.