It called for vigilance against such risks to ensure information security.
“Some individuals, after leaving their positions, disregard national security and interests, misinterpret the declassification period as a restriction of freedom or a career shackle, and even go into hiding or evade supervision,” the ministry said.
It cited a case involving a person, identified only by his surname Feng, who was sentenced to six years in prison for leaking state secrets after retiring from his job at a state-owned enterprise.
The ministry said Feng had been lured by a foreign espionage agency that offered him a substantial “consulting fee”. It said Feng had maintained close ties with his former colleagues at the company and was able to gain access to core classified information in a critical industry sector.