However, Zhang later noticed that the books were marked with the words “confidential” and “secret”. He reported the situation to the ministry and handed over the books.
The ministry said an investigation found two people, surnamed Guo and Li, from a military unit “involved in classified information” sold the materials to the recycling station.
The pair had “weak awareness of information security” and did not follow proper procedures required for destroying classified documents, the article said.
It did not say whether they faced any repercussions.
They sold more than 200 classified items weighing over 30kg (66lbs) for about 20 yuan.
The ministry praised Zhang for reporting the materials, noting that his actions prevented further dissemination of classified information and harm to military security.
The ministry added that its agencies had offered guidance to relevant units to “promptly plug the gaps in the management of information security”.
The ministry noted that China’s amended anti-espionage law required strengthening the management of information and confidential materials. The amended law came into force last July, broadening the definition of espionage and the investigative powers of state security agencies.
The ministry also cited the country’s revised law on guarding state secrets, which stipulates that creating, receiving, transferring, using, duplicating, storing, maintaining and destroying items containing state secrets should comply with relevant regulations.
The revised law came into effect last month, adding more than a dozen provisions to expand the depth and breadth of its coverage.
In Thursday’s article, the ministry also called on the public to share information about suspicious activities such as the illegal sale of items containing state secrets.
Over the past year, the ministry has become more active on social media, posting articles to warn of threats from foreign spies and educate the public about national security. It has called on the public to join the fight against spying and support implementation of the anti-espionage law.