A U.S. cybersecurity firm says it has evidence that a secretive Chinese military unit is behind a series of sophisticated hacking attacks aimed at mostly American companies. The security company, Mandiant, says the Chinese army’s Unit 61398 has perpetrated sustained attacks, stealing massive amounts of sensitive data from at least 141 different organizations. Chinese officials vehemently deny the accusations and accuse the U.S. of hacking. Though work of Unit 61398 is officially a state-controlled secret in China, it is believed to be staffed by thousands of computer programmers proficient in English and network operations …
