According to a BBC report, the 23-year-old, who was not named, was arrested in a broad initiative to capture the criminals behind Mariposa, a massive botnet that affected as many as 12.7 million computers.
Mariposa, which was designed to steal personal financial details, was dismantled earlier this year. In December, three people believed to have been running it were arrested in Spain.
"To use an analogy here, as opposed to arresting the guy who broke into your home, we've arrested the guy that gave him the crowbar, the map, and the best houses in the neighbourhood," Jeffrey Troy, deputy assistant director for the FBI cyber division, told the Associated Press.
Security expert Rik Ferguson told the BBC that the Mariposa botnet had gotten out of control. "The guys behind it said it was more successful than they had intended it to be," he said. "As is the case with most botnets, the more widespread they are, the more likely they are to be discovered. They were a victim of their own success."
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