BEIJING • Mr Ling Wancheng, the younger brother of China's disgraced former presidential aide Ling Jihua, has reportedly divulged state secrets to the United States, including how China's nuclear weapons launch system works and the personal security details of its top leaders, after fleeing to the US in late 2014.
Washington Free Beacon (WFB), a US investigative news website, reported on Wednesday that US intelligence officials have completed questioning the 56-year-old businessman and concluded that he was their most valuable defector from China in 30 years.
According to the report, Mr Ling defected to the United States with more than 2,700 copies of secret documents belonging to the General Office of the Chinese Communist Party (CCP), following the arrest of his 60-year-old brother in December 2014.
The latter, who led the General Office - which handles day-to-day logistics and bureaucratic functions of the CCP - from 2007 to August 2012, was a confidante of then president Hu Jintao, the predecessor of President Xi Jinping.
State media reported in July last year that Ling Jihua was charged with corruption and removed from the party. Another brother, Ling Zhengce, 63, a former official in Shanxi province, was placed under investigation for corruption in June 2014.
Some overseas Chinese-language media said the WFB report is perplexing as the younger Ling would only endanger the life of his brother Jihua, who is facing many criminal charges, including having received a large amount of bribes and violating political discipline, if he had indeed surrendered state secrets to the US.
"How could he bargain for a reduced punishment for Ling Jihua if all the secrets were already leaked to the US?" Radio Free Asia, which is affiliated to the US government, asked.
The secrets that Mr Ling was said to possess included the procedures that Chinese leaders must follow should they decide to use a nuclear weapon in an emergency, the report said.
Mr Ling also reportedly could provide details of the Zhongnanhai compound, where top Chinese leaders reside, and information that would help US cyber-spies access files and messages of Chinese leaders.
The WFB report said Beijing is eager to have Mr Ling repatriated because he now constitutes a huge security threat with the information he holds.
However, Chinese media has reported that it is as yet uncertain whether Mr Ling is a US citizen, which could stop him from being sent back.
The media also pointed out that Beijing might not have any grounds to arrest him as he had not committed any crime in China, unless he was found to have run away with sensitive documents.
Hong Kong dissident magazine Chengming late last year reported that Mr Meng Jianzhu, China's security czar, had disclosed at a closed-door meeting with party officials in southern China that Mr Ling had leaked vital state information to the US.