BEIJING: China's top spy agency published new details this week about a U.S. citizen jailed for life for espionage earlier this year, describing his recruitment by U.S. agents, how they fabricated his legend, and how he helped them entrap surveillance targets.

When a court in Eastern China jailed 78-year-old John Shing-wan Leung to life in May it ended his more than three decade long career as an "American spy", the Ministry of State Security wrote in a statement on its official WeChat account on Monday titled "Prominent American Spy Captured in China!".

Born in Hong Kong, Leung went to the United States in 1983 to run a restaurant, before being "formally" recruited as an informant by an unnamed U.S. spy agency in 1989 and in the same year became a U.S. citizen, the ministry's statement said.

Leung was promised $1,000 a month as well as bonuses for intelligence and a false "persona" was created to polish his "social image" to help him get close to Chinese institutions and individuals in the United States, the ministry said.

This false legend included attending university in the United Kingdom, holding a position in the United Nations and serving in the Vietnam war. The ministry said Leung was also instructed to make donations to charities and U.S. state legislators "to raise his profile".

Using this cover, the ministry said, Leung attended meals and festivals and helped organise immigrant group activities to gather intelligence on Chinese nationals and overseas Chinese in the United States.

He also brought targeted people to restaurants and hotels where surveillance devices were installed with the aim of extracting information they spilled or entrapping them.

According to the security ministry, Leung was directed to go to China by his U.S. handlers in 2020, when the pandemic restrictions made entry to the country difficult. Aged 75, Leung "used multiple identity documents to transit through Hong Kong and arrived in mainland China" in late that year, it said.

"Under the guidance of several American spies, Liang Chengyun collected a significant amount of intelligence related to China," the statement said, using his Chinese name, adding that he was given a "Meritorious Service Medal" by U.S. intelligence agencies.

The U.S. embassy in Beijing did not immediately reply to a request for comment.

The Chinese ministry did not explain in the post why it chose to share details months after Leung's conviction, but it has been conducting a national security publicity campaign with a stated aim of rooting out foreign spies and its official WeChat account only went live in August.

The release of the ministry's report on Leung coincided with a media storm in the UK after The Times of London published details about the arrest of a British parliamentary researcher suspected of spying for China.

In August, China separately released details of two investigations into Chinese nationals accused of spying for the U.S. Central Intelligence Agency (CIA).

In its statement on Leung, the security ministry warned that anyone who joins an espionage organization or accepts jobs via agents should be sentenced to at least 10 years to life in prison.

The foreign business and diplomatic community in China has become more guarded following the expansion of Beijing's anti-spying law earlier this year.