The apparently coordinated February attacks crippled some of the world's most popular sites with a barrage of messages generated by hackers. The cyber-sieges cost e-tailers hundreds of thousands of dollars in lost sales, inconvenienced millions of Internet users and raised questions about Internet security.
"This individual, using the nickname "mafiaboy," would have publicized on many occasions that he was the person responsible for those attacks," claimed Inspector Yves Roussel of the Royal Canadian Mounted Police.
Roussel said the youth had boasted in Internet chat rooms frequented by hackers about what he had done. Roussel said police obtained a search warrant and went to the boy's Montreal home on April 15.
Computers and software equipment were seized and the boy was arrested, reports CBS News Correspondent Thalia Assuras. He appeared before a Youth Court judge on Monday and was released on an undisclosed amount of bail, but with strict conditions that he use a computer only at school for schoolwork under close supervision and that he cannot go to any store dealing in computer equipment or computer use, Roussel said.
Because he is a juvenile, the suspect's real name cannot be disclosed under Canadian law.
The investigation, conducted jointly by the computer investigation unit of the RCMP and the FBI and U.S. Justice Department, was continuing, and more arrests could be made, Roussel said.
"Wherever they are, hackers will be investigated and arrested," Roussel said.
FBI spokesman William Lynn, sitting next to Roussel at a news conference, said the damage caused by such international hacking could run into the millions of dollars.
The hacking attacks involved placing tools on unwitting middleman computers and remotely ordering them to overwhelm the victim sites with fake traffic.
Former FBI agent Ed Stroz believes more such attacks are likely to occur. "All you need is access," he said. "Information is everywhere."
The U.S. attorney general issued a warning to potential young hackers. "I think it is important to look at what we do, to let young people know that they are not going to be able to get away with something like this because of age," Janet Reno said.
Three computers have been identified as middlemen in the February attacks: a computer at the University of California, Santa Barbara; a router at Stanford University; and a home business computer in the Portland, Oregon, area. Investigators say that dozens, even hundreds, of middlemen computers were used in the February attacks.
Another RCMP officer, staff Sgt. Jean-Pierre Roy, refused to provide details of how the youth took part in the attacks. He said Mafiaboy may have used a California university computer for the attack, and that he let traces of his activity that allowed police to find him.
"It is our estimation that Mafiaboy wasn't that good," Roy said. "He wasn't what we would call a genius."
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