Mark Ruffalo, Jamie Lee Curtis, and more celebs are speaking out as post-election protests erupted in Los Angeles, Chicago, New York, Philadelphia, and several other cities across the country on Wednesday.

"It begins," Curtis tweeted along with video of thousands of anti-Trump demonstrators in Chicago. "Protests and more protests."

"My niece is in Chicago is already voicing what we all are feeling!" the actress explained before ending her post with the hashtag "#notmypresident."

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Demonstrators in Trump's hometown of New York City came out in droves to denounce his presidential victory over Hillary Clinton. Ruffalo was among the thousands who attended a  "Love Fest" demonstration in front of the Big Apple's Trump Towers building.

The Avengers star Instagrammed a video of protestors packing the streets of Midtown Manhattan bearing signs that read, "Donald Trump Doesn't Speak for Me," "Wall St. Is The Enemy, Not Muslims or Immigrants," and "Liberty For All Americans, Not Hate."

The Roots drummer, Questlove, shared similar footage from Times Square. "Taking It To The Streets," he captioned video of the Big Apple protest. “Trump March Protests In Manhattan."

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Former Saturday Night Live cast member Taran Killam also shared a few different posts from NYC protests, including a selfie video which he captioned, "I love America! I LOVE New York!!!"

In keeping with the Twitter trend, Daily Show correspondent Aasif Mandavi posted some of the cities participating in “anti-Trump protests," and noted that around 10,000 protestors were heading to Trump Towers.

Taking a more straightforward approach to Trump, Charmed actress Holly Marie Combs tweeted a message to the president-elect.

"@RealdonaldTrump The protests have started," Combs wrote. "Are you paying attention? Do you hear them?"

Lady Gaga addressed Trump as well, although in a less direct manner than Combs.

"The chaos in [the] USA is the result of Trump’s irresponsible campaigning," Gaga tweeted. "He is not a role model, look at this mess he created. #LoveTrumpsHate."

Although Trump was accused of divisive homophobic, xenophobic, racist and misogynistic rhetoric throughout his presidential campaign, the 70-year-old billionaire called for unity during his victory speech early Wednesday.

"To all Republicans and Democrats and independents across this nation, I say it is time for us to come together as one united people," he said, adding a "pledge" to American citizens.

"I will be president for all Americans, and this is so important to me," promised the former reality star.

See more on Trump's big win in the video below.