Hollywood celebrities, led by Jane Fonda, used a Sunday night "Rise Up, Sing Out" concert in New York City to criticize President Donald Trump and his administration during an event held to counter the White House’s UFC Freedom 250 programming.

Fonda, who helped revive the Committee for the First Amendment, said Americans' rights were under government attack.

"This isn’t the first time that Americans’ rights have come under attack," Fonda said. "But this time, what is really different from the last century is that the attacks are coming from every part of the government: the executive, the legislative, and the Supreme Court."

She compared the moment to the House Un-American Activities Committee era of the 1950s. 

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Robert De Niro speaks at "Rise Up, Sing Out" in New York, where he criticized President Donald Trump and joked about attendees who "couldn’t get tickets to the White House cage fight." (Chris Unger/Zuffa LLC)

"I think the Un-American Activities Committee right now is coming from the White House," Fonda said.

Actress Julia Roberts paid tribute to Renee Nicole Good, a 37-year-old U.S. citizen who was shot and killed by an ICE agent during a Jan. 7 immigration enforcement operation in south Minneapolis. DHS said agents were trying to make arrests when Good allegedly tried to use her vehicle as a weapon, prompting a federal agent to fire in self-defense.

"Renee Nicole Good is not a symbol," Roberts said. "She is an American woman, a queer woman who was doing the very best she could do to be good in an unjust world."

Robert De Niro told the crowd at New York's Town Hall that he could not separate patriotism from Trump’s second term.

"I can’t love a country that’s led by Donald Trump and his sycophant Congress," De Niro said.

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Jane Fonda addresses the crowd during the First Amendment-themed concert, telling attendees that the "Un-American Activities Committee right now is coming from the White House." (Jacquelyn Martin/AP)

The actor opened by referencing the competing mixed martial arts event at the White House.

"Welcome to all of you who couldn’t get tickets to the White House cage fight," De Niro said.

De Niro said he remained devoted to the First Amendment but argued that the country had become "not so lovable right now."

The White House dismissed the celebrity criticism after De Niro, Fonda and others used the event to attack Trump and his administration.

"Nobody in their right mind cares what out-of-touch woke celebrities in Hollywood say or think," White House spokesman Davis Ingle said.

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Fans gathered for UFC Freedom 250 near the White House, where the event drew a far larger in-person crowd and Dana White said Paramount+ streaming numbers were "monstrous," while exact viewership figures had not been released. (Alex Brandon/AP)

The anti-Trump concert also leaned heavily on protest music and audience sing-along sections. During one call-and-response performance, members of Singing Resistance led the crowd through a repeated refrain.

"No one is getting left behind," the performers sang. "No one is getting left behind this time."

OutKick writer and author Ian Miller compared the event unfavorably to a conservative alternative entertainment spectacle.

"It is impossible to describe how much worse this is than Kid Rock doing an alternative Super Bowl halftime show," Miller said.

Writer and Daily Wire author Emily Zanotti reacted to the dueling spectacles.

"I truly cannot tell you which option is less of an acid trip. I know I’m not high. I know I’m not. But somehow, I don’t know," Zanotti said.

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Former West Virginia state Del. Derrick Evans said the moment reflected a broader cultural problem for Democrats.

"Why is the left always singing the dumbest things?" Evans said on X. "The left is definitely losing the culture war in America right now."

Gunther Eagleman, a conservative social media personality, called the clip "cringe and stupid."

Fonda told the crowd that "hundreds of thousands" were registering for watch parties shortly before the program, while a full YouTube stream listing for "Rise Up, Sing Out" showed about 194,000 views by Monday.

The UFC event drew far larger in-person audience metrics than the New York concert, with ESPN reporting nearly 200,000 people passed through the Ellipse over the two-day weekend and that UFC-related topics dominated X trends Sunday night, alongside the World Cup.

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UFC Freedom 250 streamed exclusively on Paramount+, and exact viewership figures had not been released by Monday. UFC President Dana White said after the event that the fights exceeded Paramount’s expectations and called the numbers "monstrous."