An anonymous reader writes "The Chinese capital city of Beijing is now a global leader in distributing viruses. According to UK-based managed security services company Network Box, Beijing accounts for 40 percent of all viruses that passed though the company's servers in June, and 5.25 percent of detected spam. This compares with slightly lower percentages for cities in countries noted for having a malware problem. Moscow was second for spam with 5.12 percent, Seoul third with 3.58 percent, Turk in Turkey fourth with 3.4 percent, and London in fifth place at 2.47 percent. 'As more and more users come online in China, there's a good chance those computers are using pirated software without up-to-date security fixes, making them prime targets for hackers who are actually located elsewhere in the world, [Simon] Heron said. Those compromised computers, which are used to send spam and make it more difficult to identify the spammer, are so valuable that hacker gangs have been competing to take over machines. If one gang finds a machine running another gang's Trojan horse program — one that appears harmless to the victim but can be used to control a machine — they'll try to remove the software.'"