A new maximum biocontainment lab in Kunming, China, was certified three years ago while remaining under-the-radar in the U.S. biodefense community, documents obtained through a Freedom of Information Act request show.

China’s plans to build an ABSL-4 under the Institute of Medical Biology and Chinese Academy of Medical Sciences in Kunming were previously known. But U.S. Right to Know can report for the first time that the lab has long been accredited by the China National Accreditation Service for Conformity Assessment, a pivotal step toward becoming operational. Animal biosafety level four, or ABSL-4, refers to the level of biosafety precautions needed to study the world’s most dangerous viruses and other pathogens in animals.

The quiet start at the Kunming lab could suggest skittishness among Chinese authorities about publicizing it due to the controversy surrounding another BSL-4 lab – the Wuhan Institute of Virology. It also underscores that international standards for reporting and transparency have lagged behind the proliferation of labs working with pandemic potential pathogens.