According to the reports, China’s Ministry of State Security codenamed the operation THUNDER 2020. It follows on the heels of an earlier counterespionage crackdown, known as THUNDER 2018, or THUNDERBOLT 2018. Last year, Chinese authorities said that the year-long 2018 operation had uncovered over 100 espionage cases throughout mainland China

The information released on Sunday includes claims that espionage activities uncovered under the THUNDER 2020 crackdown centered on “attempts to disrupt cross-Straits exchanges” —meaning efforts by China to raise support among the Taiwanese for reunification with the mainland. Other alleged espionage activities focused on encouraging “Hong Kong separatism” and on “instigating diplomatic ties between […] China and other countries”. No specific information was provided to support these claims.

In what appears to be a controlled leak, several Chinese news media reported on the case of a Taiwanese businessman identified as Li Mengju, or Lee Meng-chu. He was allegedly arrested in August of 2019 by authorities in the in southeastern Chinese city of Shenzhen, which is adjacent to Hong Kong. “Anonymous” sources in Shenzhen claim that Lee directs the “Taiwan Independence organization”, as well as another group calling itself “Taiwan United Nations Association” or “Association for the Advancement of Taiwan”. These appear to be groups that campaign against the possible reunification of Taiwan with China.

According to Chinese state-run sources, Lee was arrested “at a harbor in Shenzhen as he tried to flee after he was spotted conducting espionage activities”. He was allegedly found to be in possession of audiovisual material that had been “taken illegally” and included “secret-level military information”, such as “combat equipment, and quantity of troops”. No further information was provided by Chinese media.