Chinese cyberspies have been reading the private emails of Obama administration officials and "all top national security and trade officials" since 2010, according to a senior administration official and a top secret NSA document obtained by NBC. The email espionage — codenamed "Dancing Panda" by the US before being dubbed "Legion Amethyst" — was detected in April 2010. "The intrusion into personal emails was still active at the time of the briefing and, according to the senior official, is still going on," NBC reported. "Dancing Panda" has successfully attacked at least 600 targets over the last five years, according to...