He paid six yuan for it.
According to China's Ministry of State Security, a pensioner surnamed Zhang, who is a book collector, bought four books at a recycling center at the entrance of a house. He paid six yuan (about 0.8 dollars) for them.
At home, the man examined the newly acquired books and found that they were stamped "confidential" and "secret". Zhang contacted the local branch of the Ministry of State Security and handed the books over to the relevant authorities.
The state security officials seized all the classified materials and interrogated the person in charge of the recycling center. They found out that two employees of a certain military unit named Guo and Li, who had access to classified data, had sold the classified materials to the recycling center.
Guo and Li, trying to make their lives easier, did not destroy the classified documents as stipulated by the regulations, but simply sold the documents to the collection point for recycling.
The total weight of the surrendered documents (about 200) with confidential information amounted to more than 30 kilograms. Guo and Li's profit amounted to just over 20 yuan (about $2.75).
State security officials stopped the distribution of confidential documents. Appropriate measures were applied to all responsible persons.
Earlier, Trump promised to release classified documents about a number of terrorist attacks.