When such entities identify overseas Chinese personnel overseas, they usually approach them in three stages, the ministry said.
First, they create a “chance encounter”, where they pretend to be friendly and helpful to their targets. Then, they make frequent contact with their targets, invite them to dinners, and share information about their lives to gain trust.
Finally, when the targets have lowered their guard, the spies trick or threaten them to sell state secrets, according to the post.
“They should stay on guard about the motivations others may have when they make friends, have a strong awareness to keep secrets and resist temptations,” the ministry said.
The posts have raised alarms on a range of risks, including underwater spyware found in Chinese waters, espionage disguised as consultations and overseas students being approached to obtain information.
The ministry had previously disclosed “classic examples” of people stationed overseas who were persuaded to spy.
In April, the ministry discussed the case of Zhang Xiangbin, a translator with a Chinese ministry who was stationed in a “foreign country”. He was approached by a spy, who befriended him and later paid him for intelligence.
For years, Zhang worked as a spy in the host country and had two children with a government officer in that country, the state security ministry said.
Zhang later quit his job when he realised Chinese intelligence might have been on to him. Before leaving, he took 5,200 files and documents, many of which were designated as secret.
In 2019, Zhang was sentenced to death with a two-year reprieve.