In an exclusive article, Fox News quoted from 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 said.

The sources believe the initial transmission of the virus was bat-to-human, and that "patient zero" worked at the laboratory, then went into the population in Wuhan.

The “increasing confidence” comes from classified and open-source documents and evidence, the sources said. Fox News has requested to see the evidence directly.

Asked by Fox News about the reporting, US President Donald Trump remarked at Wednesday's coronavirus press briefing, "More and more we're hearing the story...we are doing a very thorough examination of this horrible situation."

Documents detail early efforts by doctors at the lab and early efforts at containment. The Wuhan wet market initially identified as a possible point of origin never sold bats, and the sources tell Fox News that blaming the wet market was an effort by China to deflect blame from the laboratory, along with the country's propaganda efforts targeting the US and Italy.

US 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 reported Tuesday.

Responding to the report, Gen. Mark Milley, the chairman of the Joint Chiefs of Staff, said Tuesday afternoon: "It should be no surprise to you that we have taken a keen interest in that and we've had a lot of intelligence take a hard look at that. 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."

“Even today, I see them withholding information and I think we need to do more to continue to press them to share,” Secretary of Defense Mark Esper told “America’s Newsroom" on Wednesday, referring to China.

Speaking to "The Story" Wednesday evening, Secretary of State Mike Pompeo remarked: "What we do know is we know that this virus originated in Wuhan, China. We know there is the Wuhan Institute of Virology just a handful of miles away from where the wet market was. There is still lots to learn. You should know that the United States government is working diligently to figure it out."

Concerning the State Department cables warning about the Wuhan laboratory, Pompeo said the installation "contained highly contagious materials -- we knew that, we knew that they were working on this program, many countries have programs like this. In countries that are open and transparent, they have the ability to control them and keep them safe, and they allow outside observers in to make sure all the processes and procedures are right. I only wish that that had happened in this place."

Americans were originally helping train the Chinese in a program called PREVENT well before the Chinese started working on this virus. The French government helped the Chinese set up the Wuhan lab.

China "100 percent" suppressed data and changed data, the sources tell Fox News. Samples were destroyed, contaminated areas scrubbed, some early reports erased, and academic articles stifled.

There were doctors and journalists who were "disappeared" warning of the spread of the virus and its contagious nature and human to human transmission. China moved quickly to shut down travel domestically from Wuhan to the rest of China, but did not stop international flights from Wuhan.

In the six days after top Chinese officials secretly determined they likely were facing a pandemic from a new coronavirus, the city of Wuhan at the epicenter of the disease hosted a mass banquet for tens of thousands of people; millions began traveling through for Lunar New Year celebrations.

President Xi Jinping warned the public on the seventh day, Jan. 20. But by that time, more than 3,000 people had been infected during almost a week of public silence, according to internal documents obtained by The Associated Press and expert estimates based on retrospective infection data.

A nurse holds a patient's hand to comfort her in the ICU of Zhongnan Hospital of Wuhan University in Wuhan, central China's Hubei Province, Jan. 24, 2020. Source: Xinhua/Xiong Qi

“This is tremendous,” said Zuo-Feng Zhang, an epidemiologist at the University of California, Los Angeles. “If they took action six days earlier, there would have been much fewer patients and medical facilities would have been sufficient. We might have avoided the collapse of Wuhan’s medical system.”

Additionally, the sources tell Fox News the World Health Organization (WHO) was complicit from the beginning in helping China cover its tracks.

China stifles coronavirus research?

The posts on the websites of Fudan University and the China University of Geosciences (Wuhan) were erased from online caches -- in a possible bid to control the narrative surrounding the pandemic, The Guardian reported.

The Wuhan university appeared to have published and then deleted posts about academic research that China’s ministry of science and technology needed to approve before publication.

Similar apparent censorship turned up in the form of deleted posts originally published on April 9 by the school of information science and technology at Fudan University in Shanghai.

China’s science and technology ministry had announced on April 3 that academic researchers needed to report their coronavirus findings to officials within three days or be terminated.

The news outlet noted that President Xi published an essay in March that included “tracing the origin of the virus” a national priority; the science and technology ministry referenced the essay shortly before the universities changed tunes.

On New Year’s Eve, China informed the World Health Organization of a “mysterious pneumonia outbreak” spreading through Wuhan, an industrial city of 11 million.

The Pentagon was said to have first learned about the new coronavirus in December from open-source reports emanating from China. By early January, warnings about the virus had made their way into intelligence reports circulating around the government. On Jan. 3, the head of the US Centers for Disease Control and Prevention [CDC], Robert Redfield, received a call from his Chinese counterpart with an official warning.

Dr. Anthony Fauci, the government’s top infectious disease expert, said he was alerted to the virus around the same time — and within two weeks was fearful it could bring about a global catastrophe.

Quickly, US intelligence and public health officials pressed China to allow in US epidemiologists — both to assist the country in confronting the spread and to gain valuable insights that could help buy time for the US response. US officials also pressed China to send samples of the virus to US labs for study and for vaccine and test development.

On Jan. 11, China shared the virus’ genetic sequence. That same day, the National Institutes of Health started working on a vaccine.

Ultimately, the US was able to get China’s consent to send two people on the WHO team that traveled to China later in the month. But by then precious weeks had been lost and the virus had raced across Asia and had started to escape the continent.

The coronavirus pandemic passed 2 million confirmed infections and 130,000 deaths worldwide on Wednesday — bleak markers that experts say vastly understate the true spread and toll of the contagion because of a lack of testing.

The figures have roughly doubled in 13 days and continue to grow steadily.

The actual number of cases is much higher than the official figures suggest, with countries varying in how much they are testing people./.

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