United States officials are pushing back on a new joint WHO-China study on the origins of the coronavirus pandemic, which downplays China’s involvement in the pandemic. Some officials suggest that the pandemic was the result of “gain of function” research or weaponization by the Chinese military, likely originating from a lab in Wuhan, China.

The true origin of the virus, which made its way out of Wuhan, China, is currently the subject of a joint investigation by the World Health Organization and Chinese authorities. The joint study claims that the theory suggesting the virus escaped from a Wuhan-based lab is the least likely theory out of four possible theories posited by the study.

The report contends that the most likely source of the virus comes from human contact with an animal that carried the exotic disease, and that the lab leak theory is “extremely unlikely.” The report suggests that a bat infected another animal, which then infected a human.