China on Tuesday said it has been “open and transparent” in the search for the origins of COVID-19, after questions about how the pandemic began received new attention.

Most recently, the U.S. Department of Energy assessed with “low confidence” that the pandemic that was first detected in the central Chinese city of Wuhan in late 2019 began with the leak of a virus from a lab. The report hasn’t been made public.

China had “shared the most data and research results on virus tracing and made important contributions to global virus tracing research,” Foreign Ministry spokesperson Mao Ning Mao told reporters at a daily briefing.

“Politicizing the issue of virus tracing will not smear China but will only damage the U.S.’s own credibility,” Mao said, in response to complaints from U.S. officials and members of Congress that China has not been entirely cooperative.

Her comments came amid continuing questions about how the virus that has killed more than 6.8 million people worldwide first emerged.

Also Read: Coronavirus origins still a mystery 3 years into pandemic

Others in the U.S. intelligence community disagree with the U.S. Energy Department assessment of the lab leak, citing differing opinions within the government. “There is just not an intelligence community consensus,” John Kirby, the spokesman for the National Security Council, said Monday.

Others in the U.S. intelligence community disagree with the U.S. Energy Department assessment of the lab leak, citing differing opinions within the government. “There is just not an intelligence community consensus,” John Kirby, the spokesman for the National Security Council, said Monday.