Authorities have smashed one of the world's biggest networks of virus-infected computers, 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 and more than 40 major banks, 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. The arrests are significant because the masterminds behind the biggest botnets aren't often taken down. And the story of investigators' hunt for them offers a rare glimpse at the tactics used to trace the origin of computer crimes. The three suspects were described as Spanish citizens with no criminal records. Authorities identified them by their Internet handles and their ages: “netkairo,” 31; “jonyloleante,” 30; and “ostiator,” 25.
