Eurasia Group's Jeremy Chan told Insider that "so much remains unknown about Qin's case."
As of press time, references to Qin had been removed from the foreign ministry's website.
China's foreign ministry did not immediately respond to a request for comment from Insider.
Because of the opacity of the Chinese government, few people will ever know what led to Qin's abrupt departure, experts say.
Chong Ja Ian, an associate professor at the National University of Singapore, told Insider that the lack of clarity "is part of the opacity and uncertainty" in China.
Persons:
Qin Gang, Jeremy Chan, Qin, Wang Yi, Wang, Chong Ja Ian, Chong, Dylan Loh, Loh, Wang Wenbin, Wang's, Fu Xiaotian, Fu
Organizations:
Eurasia, Service, Qin, Eurasia Group, National University of Singapore, Nanyang Technological University, Twitter
Locations:
Wall, Silicon, China's, China, Beijing, Russia, Vietnam, Sri Lanka, Indonesia, Chinese, South China