(AP) -- Authorities have smashed one of the world's biggest networks of virus-infected computers. It was a data vacuum that stole credit cards and online banking credentials from as many as 12.7 million poisoned PCs.
The "botnet" of infected computers included PCs inside more than half of the Fortune 1,000 companies. More than 40 major banks were infiltrated, according to investigators.
Spanish investigators, working with private computer-security firms, have arrested the three alleged ringleaders of the so-called Mariposa botnet, which appeared in December 2008 and grew into one of the biggest weapons of cybercrime.
More arrests are expected soon in other countries. That is unusual - the masterminds behind the biggest botnets aren't often taken down.
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