One of the investigator sources said the secret military-funded experiments on the mine virus, RaTG13, began in 2016. At around that time, the Wuhan institute became even less open about its work and mostly stopped revealing any new coronaviruses it discovered. In the lead-up to the pandemic, the Wuhan institute frequently experimented on coronaviruses alongside the Academy of Military Medical Sciences, a research arm of the People’s Liberation Army (PLA). In published papers, military scientists are listed as working for the Beijing Institute of Microbiology and Epidemiology, which is the military academy’s base.