Bloomberg Businessweek has a remarkable story about the identification of another Chinese hacker. It’s a long, tangled, and fascinating tale of good sleuthing by several researchers, but the trail ends with Zhang Changhe, a digital entrepreneur and teacher — at a People’s Liberation Army school that is suspected of training PLA hackers.

In the denouement, Bloomberg actually calls the guy on his mobile phone and gets partial confirmation of the evidence assembled by security researchers:

A Chinese-language search on Google turns up a link to several academic papers co-authored by a Zhang Changhe. One, from 2005, relates to computer espionage methods. He also contributed to research on a Windows rootkit, an advanced hacking technique, in 2007. In 2011, Zhang co-authored an analysis of the security flaws in a type of computer memory and the attack vectors for it. The papers identified Zhang as working at the PLA Information Engineering University. The institution is one of China’s principal centers for electronic intelligence, where professors train junior officers to serve in operations throughout China, says Mark Stokes of the Project 2049 Institute, a think tank in Washington. It’s as if the US National Security Agency had a university.

The gated campus of the PLA Information Engineering University is in Zhengzhou, about four miles north of Zhang Changhe’s mobile shop. The main entrance is at the end of a tree-lined lane, and uniformed men and women come and go, with guards checking vehicles and identification cards. Reached on a cell-phone number listed on the QQ blog, Zhang confirms his identity as a teacher at the university, adding that he was away from Zhengzhou on a work trip. Asked if he still maintained the Henan Mobile telephone business, he says: “No longer, sorry.” About his links to hacking and the command node domains, Zhang says: “I’m not sure.” About what he teaches at the university: “It’s not convenient for me to talk about that.” He denies working for the government, says he won’t answer further questions about his job, and hangs up.