On the September 12, 2019, the virus database at the Wuhan Institute of Virology was taken offline, and with it 22,000 coronavirus samples were gone.
That same day security was beefed up at the facility and a tender was issued to replace the air-conditioning system. There was later a communications blackout, with no cell-phone or signals activity.
The institute also went on a spending spree, purchasing an air medical waste incinerator and PCR equipment to test for coronaviruses.
One of those three researchers working at the Wuhan Institute of Virology was Huang Yanling, who disappeared from the institute's website in early 2020.
Her social media presence also vanished. She has not been seen since.
https://www.skynews.com.au/world-news/global-affairs/the-lab-leak-the-missing-scientists-the-coverup-piecing-together-what-really-happened-in-wuhan/news-story/122d7cab3d2db39103d75085edb85195
What happened in Wuhan September 12, 2019