Dr. Anthony Fauci, the US government's top infectious disease specialist, furiously accused a senator Tuesday of fabricating false allegations that have resulted in threats against him — all in the name of raising political money.

Sen. Rand Paul of Kentucky, a Republican, has frequently asserted that Fauci lied about the epidemic and stated in a hearing Tuesday that he attempted to "takedown" sure scientists who disagreed with him.

Paul and other conservative opponents have targeted Fauci, the infectious disease chief at the National Institutes of Health, serving as President Joe Biden's chief medical adviser. Since 2020, Fauci has required additional protection due to threats and harassment directed at him and his family.

Tuesday, Fauci expressed frustration that the senator continues to "accuse me of things that are completely untrue" and "inspires the crazies out there" this deep into the pandemic.

He cited the arrest last month of a California man pulled over for speeding in Iowa and informed a sheriff's office that he was going to the nation's capital to assassinate a list of influential people, including Fauci. According to court filings, the man, Kuachua Brillion Xiong of Sacramento, was in the car with an AR-15-style gun, ammunition, and body armor.

Paul's website, Fauci said, includes a "fire Dr. Fauci" page and a request for political contributions ranging from $5 to $100.

Paul, he charged, was exploiting the virus "for your political gain."

The feud overshadowed a Senate Committee on Health, Education, Labor, and Pensions hearing to determine whether policy changes are necessary as the US battles the highly contagious omicron strain.

Among Republicans and Democrats' primary grievances is the continued absence of testing that makes it easier for people to determine if they have COVID-19 and hence stay home and avoid spreading it.

"I just want to say to everyone right now that testing is broken," an angry Sen. Richard Burr, R-North Carolina, the committee's top member, said.

Nonetheless, Burr and several other legislators on both sides of the aisle expressed gratitude to Fauci for his efforts to combat the pandemic.

However, Fauci lost his temper later in Tuesday's meeting when Sen. Roger Marshall, R-Kansas, accused him of concealing financial disclosure forms required of public officials.

"You are extraordinary in your ignorance," Fauci remarked, noting that those materials are publicly available upon request. As the exchange concluded, Fauci was heard off-camera mumbling, "What a moron."