There is “increasing confidence” that coronavirus likely originated in a Wuhan laboratory as part of China’s effort to demonstrate that its efforts to identify and combat viruses are equal or greater than the capabilities of the United States, according to a report in Fox News.

Fox News’ report is based on “multiple sources who have been briefed on the details of early actions by China’s government and seen relevant materials.”

This may be the “costliest government coverup of all time,” one of the sources told Fox News.

The report said the sources do not believe the coronavirus was a bioweapon, but that “patient zero” at the laboratory contracted the virus from a bat at the lab, then went into the population.

The “increasing confidence” comes from classified and open-source documents and evidence, the sources said. Fox News has “requested to see the evidence directly,” indicating that it has not yet seen any evidence directly.

U.S. officials have equivocated in recent days on whether they believe the coronavirus pandemic originated from the lab.

When asked about the prospect earlier this week, Secretary of State Mike Pompeo said: “Look, there’s still lots of work to be done to find out precisely what happened here, precisely how this came to be.”

Asked the same question, Chairman of the Joint Chiefs of Staff Gen. Mark Milley said, “We’ve had a lot of intelligence take a hard look at that. And I would just say at this point it’s inconclusive, although the weight of evidence seems to indicate natural. But we don’t know for certain.”

Defense Secretary Mark Esper told Fox News on Wednesday: “Most people believe it began naturally — it was organic, if you will. I think in due course, once we get through the pandemic we’re in right now, there’ll be time to look back and really ascertain what happened.”

Also on Wednesday, President Trump said: “More and more we’re hearing the story…we are doing a very thorough examination of this horrible situation.”

Fox News’ report said the documents detail early efforts by doctors at the lab and early efforts at containment, and the Wuhan wet market’s identification as the possible point of origin was an effort by China to deflect blame from the laboratory.

Videos of Chinese people eating bat soup flooded social media shortly after the outbreak became public. But according to Fox News and other recent reports, the wet market never sold bats.

U.S. Embassy officials warned in January 2018 about inadequate safety at the Wuhan Institute of Virology lab and passed on information about scientists conducting risky research on coronavirus from bats, the Washington Post first reported Tuesday.

The report also suggested the Chinese government tried to cover up something.

Sources told Fox News that China suppressed and changed data. They said samples of the virus were destroyed, contaminated areas scrubbed, early reports erased, and academic articles stifled.

The report also noted that doctors and journalists who warned of the virus were “disappeared,” and China quickly shut down travel domestically from Wuhan to the rest of the country but did not stop people from Wuhan traveling outside of China.

The sources also told Fox News the World Health Organization (W.H.O.) as “complicit from the beginning in helping China cover its tracks.”

The story also noted reporting from the Associated Press, which said that on January 19 — six days after top Chinese officials secretly determined they were likely facing a pandemic — they still allowed Wuhan to host a mass banquet for tens of thousands of people.

China first alerted the W.H.O. of the coronavirus on December 31. However, according to the AP report, there was a nearly two-week period where the Chinese Center for Disease Control did not register any cases from local officials.

During that time, from January 5 to January 14, “hundreds of patients” were appearing in hospitals in Wuhan and across the country, according to the AP.

There was then another six-day delay before Chinese President Xi Jinping acknowledged the outbreak, on January 20. The AP reported that “by that time, more than 3,000 people had been infected during almost a week of public silence.”

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