China has refused requests by the World Health Organization to take part in an investigation into the origins of the coronavirus.

Axar.az reports citing foreign media that the WHO and the U.S. intelligence community have concluded that the coronavirus is naturally-occurring and was not genetically engineered. However, U.S. officials suspect that the pathogen may have been accidentally from a lab, possibly the Wuhan Institute of Virology or the Wuhan Center for Disease Control.

“We know that some national investigation is happening but at this stage we have not been invited to join,” Dr. Gauden Galea, WHO representative in China, told Sky News. “WHO is making requests of the health commission and of the authorities.”

Laboratory logs “would need to be part of any full report, any full look at the story of the origins,” Dr. Galea said. The WHO representative emphasized that “the origins of virus are very important, the animal-human interface is extremely important and needs to be studied. The priority is we need to know as much as possible to prevent the reoccurrence.”