FIRST ON FOX: House Republicans are pressing ahead with their probe of federal taxpayer dollars funding risky coronavirus research by China's Wuhan Institute of Virology in a new letter they sent Thursday to the acting director of the National Institutes of Health (NIH).

GOP leaders on the House Energy and Commerce Committee are zeroing in on EcoHealth Alliance, a New York-based research nonprofit that secured millions in federal funds to conduct research, including with the Wuhan Institute of Virology in China.  

Peter Daszak and Thea Fischer, members of the World Health Organization (WHO) team tasked with investigating the origins of the coronavirus disease (COVID-19), sit in a car arriving at Wuhan Institute of Virology in Wuhan, Hubei province, China February 3, 2021. REUTERS/Thomas Peter

Peter Daszak and Thea Fischer, members of the World Health Organization (WHO) team tasked with investigating the origins of COVID-19, sit in a car at the Wuhan Institute of Virology in Wuhan, China, Feb. 3, 2021. (Reuters/Thomas Peter)

In a detailed 10-page letter to Lawrence Tabak, the acting director of NIH, the Republicans sound the alarm about EcoHealth withholding information from the NIH about its research activities, including risky research on humanized mice at the Wuhan Institute of Virology.

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The letter raises alarms about EcoHealth Alliance withholding data from a federal government database on its research, and whether EcoHealth was double-billing both the NIH and U.S, Agency for International Development (USAID) for the work and EcoHealth receiving private donations that may have been unreported to NIH.

Rep. Cathy McMorris Rodgers

Rep. Cathy McMorris Rodgers testifies during a Republican-led forum on the origins of the COVID-19 virus at the Capitol on June 29, 2021. (Kevin Dietsch/Getty Images)

"New information from recently disclosed information included in the recent NIH letters raises troubling concerns about EcoHealth’s conduct upon which the NIH is either overlooking or taking insufficient action," the lawmakers wrote to the NIH in a letter obtained by Fox News Digital. 

"Those concerns include withheld data and possible double billing, missing laboratory notebooks and electronic files related to humanized mice research at the Wuhan lab, and EcoHealth’s private donations that may not have been reported to NIH."

The lawmakers continued: "These concerns raise the prospect of possible fraud that require the NIH’s heightened attention."

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EcoHealth Alliance and NIH did not immediately respond to Fox News' request for comment.  

The questions are the latest in the Republicans' ongoing probe of the origins of the COVID-19 pandemic. The letter was led by House Energy and Commerce Committee Republican leader Cathy McMorris Rodgers, R-Wash., Subcommittee on Health Republican leader Brett Guthrie, R-Ky., and Subcommittee on Oversight and Investigations Republican leader Morgan Griffith, R-Va.

There are two competing theories of how COVID-19 started: naturally or through a lab release. Scientists are not in agreement, while the U.S. intelligence community also could not draw conclusions on what started the global pandemic that has killed more than 5.9 million people worldwide.

Knowing the origins could help determine how to prevent future pandemics and also develop public policy to potentially hold China accountable for the global pandemic. If risky lab research is associated with the creation of the novel coronavirus, then policymakers would have further motivation to regulate or potentially stop federal funding for gain-of-function research and make grantees more accountable. 

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While China is not cooperating and has denied the lab leak theory, investigators in the U.S. believe they can gain critical information from EcoHealth Alliance, which received $117 million from U.S. taxpayers, and has conducted research with the Wuhan Institute of Virology, according to a Republican House aide. 

Anthony Fauci at White House, COVID response team

Dr. Anthony Fauci participates in the White House COVID-19 Response Team's call with the National Governors Association from the White House campus on Dec. 27, 2021. (AP Photo/Carolyn Kaster)

Republicans, in the minority and without subpoena power, have been frustrated with what they say is a lack of cooperation from both NIH and EcoHealth Alliance on providing necessary information on the type of research that was happening at the Wuhan lab prior to the coronavirus outbreak in China. The NIH also has called out EcoHealth Alliance for failing to cooperate and stopped the grant funding in 2020. 

Under a lab-leak theory, the coronavirus virus would have originated from the Wuhan Institute of Virology, which studies bat coronaviruses and has engaged in risky gain-of-function research. The virus could have spread from a researcher accidentally getting infected during an experiment and then unleashing it into the community.

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Once dismissed as a conspiracy, the lab-leak theory is gaining more steam, with the United Kingdom government now believing the Wuhan lab leak is the most likely COVID-19 origin, according to a new report in the British newspaper the Telegraph.

"I think the official view [within Government] is that it is as likely as anything else to have caused the pandemic. A lot of people like myself think it is more likely. I think attitudes have changed a little bit. The zoonotic transfer theory just didn’t make sense," Cambridge bio-security fellow Hamish de-Bretton Gordon told the paper

Fox News' Timothy H.J. Nerozzi contributed to this report.