>> beijing has accused the u.s. of politicizing the pandemic, vehemently denying the possibility of a wuhan lab leak. >> the u.s. should invite w.h.o. experts to investigate fort dietrich. >> chinese officials call for the world health organization to investigate a lab leak at the u.s. army medical research institute in maryland. backed by an aggressive social media campaign directed from beijing. to be clear, there is zero evidence to support that notion. >> the politics of this have taken a life of its own. we need to make it back to the science. >> one of the things that keeps coming back to, you want science, evidence, data, the database of bat coronaviruses was taken down and blood samples from workers at the lab, they don't have access to those. they can't do a forensics examination of the lab. but if they don't give the most basic data, how is it science driven?