Dr. Anthony Fauci enjoyed multiple years of U.S. Marshals protection, but that security is now "winding down," Fox News has learned.

A source briefed on Fauci's security informed Fox News of the incoming rollback but declined to offer details on exactly when security will end. The National Institutes of Health (NIH) requested security for Fauci in 2020, and he has been under U.S. Marshals protection since then.

U.S. Marshals kept protecting Fauci even after he left public office due to his recent testimony on Capitol Hill. They noted that he has received countless death threats in the years since the COVID-19 pandemic.

News of the wind-down comes after Republicans blasted Fauci for still having security on the taxpayers' dime. They also argued his complaints of death threats were an attempt to garner sympathy.

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Fauci testified before Congress this month. Lawmakers on the House Oversight Select Subcommittee on the Coronavirus Pandemic grilled him throughout the hearing, which focused on the U.S. Centers for Disease Control and Prevention's 6-feet distancing rule, the masking of schoolchildren and other pandemic-era restrictions. 

Fauci responded affirmatively each time when asked by Rep. Michael Cloud, R-Texas, whether business closures, church closures, school closures and stay-at-home orders were justified, adding that "again, this was when we were trying to stop the tsunami of deaths that were occurring early on – how long you kept them going is debatable." 

"Mask mandates for children under the age of 5? There’s scientific evidence supporting that?" the congressman asked.

FAUCI ADVISER'S ALLEGED DESTRUCTION OF COVID ORIGIN DOCS MUST BE PROBED BY AG: RAND PAUL

"There was no study that did masks on kids before," Fauci said. "You couldn’t do the study. You had to respond to an epidemic that was killing 4-5,000 Americans a day." 

The Republican-led subcommittee has spent over a year probing the nation’s response to the pandemic and whether U.S.-funded research in China may have played any role in how it started. Democrats opened the hearing by saying the investigation so far has found no evidence that Fauci did anything wrong, while missing an important opportunity to prepare for the next outbreak.

Fox News' Danielle Wallace contributed to this report.

Tennis legend Martina Navratilova fired back at a reporter who labeled her "transphobic" on Friday as she campaigned with the Independent Women’s Forum as part of its "Take Back Title IX" initiative.

Ben Rothenberg, a tennis journalist who is now a podcast host and wrote a Naomi Osaka biography, offered his take on Navratilova’s involvement with the women’s organization after the group’s bus was vandalized in North Carolina.

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"Martina Navratilova turning this anti-trans crusade into her life's obsession in recent years remains dispiriting!" Rothenberg wrote. "And she turns it into way more transphobic vitriol than just discussing sports fairness, as I've covered before, just being nasty and cruel and dehumanizing. Boo."

Navratilova responded later Friday night.

"Yet another man telling women what they should care about," Navratilova wrote. "And who are you exactly? Oh yeah, the reporter who tells tennis players its off the record and then prints what they said anyway. Good to know you care about women’s sports and women’s sex based spaces. I care."

Rothenberg responded to Navratilova.

"I’ve never done that. But I care also, about someone who was a beacon of freedom and inclusion in the sport I’ve covered sadly choosing to erode the platform she built with cyberbullying campaigns aimed at obscure, low-level amateur athletes. I wish you were better than that."

Navratilova seemingly took issue with the assertion she was "cyberbullying."

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"Cyber bullying- wow. I am blocking you once and for all. For your information I am doing a whole lot more than just tweeting. You can just go away now. Hope I see your nasty self at Wimbledon- if you are there."

Navratilova is a pioneer in the lesbian and gay community and in women’s tennis. She’s advocated for fairness in women’s sports amid the debate over transgender participation.

She applauded World Athletics last year for developing an open category for transgender athletes. She wrote in an op-ed it was a "step in the right direction."

"In the wake of World Athletics’ announcement, I think the best idea would be to have ‘biological female’ and ‘biological girls’ categories and then an ‘open’ category," she wrote. "It would be a category for all-comers: men who identify as men; women who identify as women; women who identify as men; men who identify as women; non-binary – it would be a catch-all. This is already being explored in athletics and swimming in Britain.

"Biological females are most likely to compete in the biological female category, as that’s their best shot at winning and it maintains the principle of fairness. With an ‘open’ category there are no question marks, no provisos, no asterisks, no doubts. It’s a simple solution.

"Once somebody has gone through male puberty, there is no way to erase that physical advantage. You cannot simply turn back the clock, for instance by trying to lower testosterone levels."

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