The arrest of the juvenile, whose identity was sealed from the public, was for "intentionally causing damage and attempting to cause damage to protected computers," a federal offence, said John McKay, United States Attorney for the
Western District of Washington.
"Computer hackers need to understand that they will be pursued and held accountable for malicious activity, whether they be adults or juveniles," McKay said in a statement in Seattle on Friday.
The Washington Cyber Task Force, which includes local law enforcement, the Seattle Division of the FBI and the secret service participated in the investigation with the assistance of Microsoft, McKay said.
The arrest comes a week after Jeffrey Lee Parson, a Minnesota teenager suspected of creating another variant of the destructive Blaster worm, was indicted in a Seattle court on one count of causing damage to a computer.
Parson, 18, a burly high school senior from Hopkins, Minnesota, has pleaded not guilty to the charge of intentionally causing or attempting to cause damage to a computer. He faces a maximum of 10 years in prison and a $250,000 fine if convicted.
Blaster and its variants are self-replicating Internet worms that bore through a Windows security hole.
"Billy Gates why do you make this possible? Stop making money and fix your software!!"
Blaster virus message
Details of the investigation were also sealed, but authorities said the juvenile had released a variant of the Blaster worm called RPCSDBOT, which told infected computers to launch a denial of service attack on Microsoft's Web site.
The attack targeted a Microsoft update page that would have fixed the flaw, but Microsoft had changed its Web address in order to thwart the attack.
The virus also carried a message to Bill Gates, the Microsoft founder and chairman, saying: "Billy Gates why do you make this possible? Stop making money and fix your software!!"
The virus spread to hundreds of thousands of computers around the world in mid-August and was among a series of worms that clogged the Internet, causing an estimated $5 million to $10 million in damage.
It forced computer shutdowns at the Federal Reserve Bank of Atlanta, Georgia and the Maryland state motor vehicle offices.
The recent spate of viruses, including the Blaster and SoBig worms, have experts worried about the new breed of virus, which spreads quickly and clogs computer networks, with the potential for hackers to take control of thousands of computers.