The US authorities stated he deleted critical files from operating systems , which shut down the United States Army 's Military District of Washington network of 2,000 computers for 24 hours . McKinnon also posted a notice on the military 's website : " Your security is crap " . After the September 11 attacks in 2001 , he deleted weapons logs at the Earle Naval Weapons Station , rendering its network of 300 computers inoperable and paralyzing munitions supply deliveries for the US Navy 's Atlantic Fleet . McKinnon was also accused of copying data , account files and passwords onto his own computer . US authorities stated the cost of tracking and correcting the problems he caused was over $ 700,000
September 11 attacks
September 11 attacks
Gary McKinnon