BEIJING (AP) -- A military history buff in China appears to have made an alarming discovery after picking up four discarded books for less than $1 at a neighborhood recycling station: They were confidential military documents. The country's Ministry of State Security told the story in a social media post on Thursday, praising the retired man for calling a hotline to report the incident. It identified him only by his family name, Zhang, and did not say what the documents were about.