The U.K. approved an extradition request this week to send a computer hacker to the United States, where he'll be tried for allegedly crippling military networks shortly after the terrorist attacks in September 2001.

Gary McKinnon, 40, of London, has freely discussed his hacking exploits that led to the seizure of his equipment in March 2002. McKinnon, who admitted probing networks but claims he did no damage, fought extradition on the grounds he could be classified as an enemy combatant and held under similar conditions as other terrorist suspects held by the United States.

McKinnon has two weeks to appeal. If extradited, he will face trial in the U.S. District Court for the Eastern District of Virginia.

The U.S alleges that McKinnon gained access to 97 government computers between February 2001 and March 2002, copying files and deleting data. The systems included those used to replenish munitions and supplies for the U.S. Navy's Atlantic fleet and the NASA space agency.

In one incident, McKinnon allegedly deleted system files and logs that shut down 300 computers at a U.S. Navy base "at a critical time" immediately after the Sept. 11 attacks, according to court documents. His alleged exploits are estimated to have caused more than $US700,000 in damage in total.

McKinnon, who went by the nickname "Solo," used a program called "RemotelyAnywhere" to control computers and access files. The former systems administrator said the networks he accessed often had low security, with easy-to-guess administrator passwords.

McKinnon said he continued to hack even after his probed had been noticed. On one occasion he miscalculated the time zones between the U.S. and the U.K., accessing a computer while someone was using it. The connection was immediately cut by the user, McKinnon said.