Indicted Chinese hacker UglyGorilla Wang Dong leaves telltale signs of himself throughout the internet

Prosecutors building a case against Wang Dong, one of five Chinese military hackers indicted for economic espionage, were helped by Wang's apparent willingness to break a cardinal rule of spying: Leave no tracks.

Known as UglyGorilla, Wang is a pun-making hacker who left a string of clues dating back years, according to several security professionals who have pursued him. He became famous in counterintelligence circles as China's most flamboyant hacker, as he seeded malicious code with his handle and left the initials "UG" in the logs of thousands of compromised computers.

Last week, the US Justice Department unveiled the indictment of the People's Liberation Army officers it says broke into computers at five US companies, including Westinghouse and United States Steel, to steal trade secrets and other information.

Among those indicted was a hacker the prosecutors identified as Wang, also known as UglyGorilla - the first time the government had linked the two names. The indictment cast a public spotlight on a hacker who for years had left a trail that was obvious to those more accustomed to scrutinising wisps of digital information for clues.

"When the indictment came out, my wife asked me if I knew this UglyGorilla guy," said Adam Meyers, who first encountered China's cyberspies as a security specialist at the US State Department. "I told her, 'I've known him longer than I've known you,'" said Meyers, who celebrates his three-year wedding anniversary next week.