An associate professor at the University of Technology in Sydney Feng has been described as anything but a Chinese dissident.
Fellow academic Professor John Fitzgerald says, rather, Dr Feng is a loyal Chinese patriot.
"He's committed to China, his support of the Chinese Communist Party. He's ... shall we say, he's on the reform wing of the Chinese Communist Party."
But back in his homeland for a research tour, it appears his work has been enough to draw the attention of Chinese authorities, who are not letting him leave the country.
A friend, John Hugh, says he has spoken to Dr Feng and his wife by telephone.
"I asked him if he's going to be interviewed by the Chinese authorities again. He said, yes definitely will be."
Mr Hugh says the UTS academic was first questioned early in his trip a week ago.
"He was requested to undergo a lie-detector polygraph, and Dr Feng declined it. So the Yunnan secret police then followed him all the way to Guangzhou."
There, in the southern city, Dr Feng reportedly tried twice to board planes on Friday and Saturday (march 24-25) but was prevented from doing so.
His lawyers say he was told he was under suspicion of threatening state security.
Dr Feng is a member of the group Australian Values Alliance, and John Hugh says he believes the academic's criticism of China's influence in Australia has attracted China's attention.
"We are very much concerned. Whatever we do, whatever we say here in Australia, we have not broken Chinese law."
The stand-off coincides with Chinese premier Li Keqiang's current visit to Australia and New Zealand.
Mr Li has encouraged Chinese-Australians to act as what he calls "friendly envoys" between the two countries.
Colleagues say the timing is curious but they doubt the visit is connected to Dr Feng's issue.
