A PLA general has made startling revelations about a flurry of scandalous espionage cases over the past decade, shedding rare light on a long list of senior cadres, diplomats and military officers allegedly spying for other countries. Most of the espionage cases mentioned by Major General Jin Yinan were deemed classified, including ones involving a former head of the nation's nuclear programme and a former ambassador, with many shocking details made public for the first time. The revelations were believed to have been made by Jin, director of the Strategic Teaching and Research Department at the National Defence University, during a recent internal government briefing. It remains unclear how video clips of his 150-minute speech were posted on the internet. It is widely available on global sites like YouTube, but has been purged from video providers in China such as Youku.com and Tudou.com. According to Jin, Kang Rixin, general manager of China National Nuclear, was one of the most senior officials involved in espionage cases in the nation's history. While state media said Kang was jailed for life late last year on bribe-taking and other unspecified corruption charges, Jin said Kang was involved in selling critical national secrets about China's nuclear power industry to foreign countries. The case of Kang - who was a member of the Communist Party's elite Central Committee and the Central Disciplinary Committee - dropped a political bombshell within the party's innermost circle, and prompted President Hu Jintao to launch a sweeping investigation of top party and government officials. 'Kang's case can't be made public because the damage he has done by selling secrets was a lot more devastating than economic losses,' Jin said in the speech. Rumours were rife on the internet after the arrest of Kang in 2009 that he had leaked 'business secrets' to international nuclear power companies from France and the US in 2006, during the public tender process for two nuclear projects worth up to 1.8 billion yuan (HK$2.2 billion). Jin also provided a glimpse into a case involving former ambassador to South Korea Li Bin, which the general said rocked leadership and diplomatic circles. Li was detained in 2007 for leaking state secrets to Seoul, according to South Korean press reports, but he was sentenced to seven years in prison on unspecified economic charges instead, according to Jin. 'We could only talk about his involvement in economic problems in public, because the case was way too humiliating and damaging to make public,' Jin said. 'Have you ever heard of an ambassador spying for a foreign country?' Li's spying left China in a difficult position during the six-party talks on North Korea's nuclear programme, which 'seriously compromised' key national interests, the general added. Jin mentioned several other high-profile espionage cases, including Cai Xiaohong, a former senior official with Beijing's liaison office in Hong Kong, Senior Colonel Xu Junping and former Chinese Academy of Social Sciences researcher Lu Jianhua. Cai was sentenced to 15 years in prison in 2004 for supplying state secrets to a British intelligence service long before the handover of Hong Kong. Xu, who worked in the foreign affairs office in the Defence Ministry, defected to the US in 2000, which was viewed as a major blow to Beijing as 'Xu was believed to have been familiar with the personality of top mainland leaders and their habits in making decisions', according to Jin. Jin said that sociologist Lu, who was sentenced to 20 years in jail on espionage charges after a closed trial, had worked for five foreign governments, including the US, Japan and Taiwan. The general lamented a moral decline as a result of economic reform and opening up, and warned that the government had to be on high alert for further espionage cases endangering national security.