(CNN) For many Americans across the country, Donald Trump's victory is an outcome they simply refuse to accept.

"Not my president," protesters chanted in rallies coast to coast.

Tens of thousands filled the streets in at least 25 US cities overnight -- with demonstrations outside Trump's properties.

While most protesters were peaceful, dozens were arrested. At least three officers were wounded. And about 40 fires were set in one California city.

Here's a snapshot of the rallies across the nation:

NY: Thousands march outside Trump's home

On Thursday afternoon, more than 200 anti-Trump protesters marched from the Union Square area to Washington Square Park in Manhattan.

Some carried signs with messages such as, "White men stop ruining everything." They chanted, "Trump and Pence make no sense."

#unionsquare #blm #notrump #protest #midterms A video posted by Just Coline (@coline____j) on Nov 10, 2016 at 10:28am PST

Overnight, about 5,000 people protested the real estate mogul's victory outside Trump Tower, authorities estimated. They included pop star Lady Gaga, a staunch Hillary Clinton supporter.

Lady Gaga protests against Donald Trump early Wednesday outside Trump Tower in New York.

Their concerns ranged from policies, such as Trump's proposed plan to build a wall along the US-Mexican border, to the polarizing tenor of his campaign that they say stoked xenophobic fears.

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"I came out here to let go of a lot of fear that was sparked as soon as I saw the results," protester Nick Powers said in New York. He said he feared Trump will support stronger stop-and-frisk policies that would put many people in prison. Powers said he was also worried that Trump's victory would embolden sexist views.

At least 15 protesters at Trump Tower were arrested Wednesday night for disorderly conduct, New York police said.

Oakland, California: 40 fires started

About 7,000 demonstrators filled streets in Oakland on Wednesday night -- and some turned violent.

Protesters hurled Molotov cocktails, rocks and fireworks at police. Three officers were injured, police spokeswoman Johnna Watson said.

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Trash fires smoldered on a highway, and a downtown business was set ablaze. By Thursday morning, emergency workers extinguished about 40 fires.

"Throughout the evening, the large group splintered into smaller groups that began vandalizing numerous businesses in the downtown area," Oakland police said.

Photos: Anti-Trump protests after election Photos: Anti-Trump protests after election Nearly 1,000 students and faculty members at Rutgers University staged a rally in downtown New Brunswick, New Jersey, to protest President-elect Donald Trump on Wednesday, November 16. At least 25 US cities have seen protests since Trump won the presidential election. Hide Caption 1 of 30 Photos: Anti-Trump protests after election Students hold signs in front of the Supreme Court in Washington during a protest on Tuesday, November 15. Hide Caption 2 of 30 Photos: Anti-Trump protests after election Activists use a banner to block traffic on Interstate 395 during an anti-Trump protest in Washington on Monday, November 14. Hide Caption 3 of 30 Photos: Anti-Trump protests after election Anti-Trump protesters in New York hung an upside-down American flag from the side of the Manhattan Bridge on November 14. Hide Caption 4 of 30 Photos: Anti-Trump protests after election Demonstrators distribute safety pins as a sign of solidarity against intolerance during a rally against Trump in New York on Saturday, November 12. Hide Caption 5 of 30 Photos: Anti-Trump protests after election Demonstrators march to Trump Tower in Chicago on November 12. Hide Caption 6 of 30 Photos: Anti-Trump protests after election People protest Trump during a march in downtown Miami on Friday, November 11. Hide Caption 7 of 30 Photos: Anti-Trump protests after election Hundreds of Trump protesters hold a demonstration in New York's Washington Square Park on November 11. Hide Caption 8 of 30 Photos: Anti-Trump protests after election A man walks by anti-Trump graffiti in downtown Oakland, California, on November 11. Thousands of protesters have wreaked havoc on the city during anti-Trump marches, causing vandalism, fires and destruction of property. Hide Caption 9 of 30 Photos: Anti-Trump protests after election A protester kicks the window of a Bank of America branch in Portland, Oregon, on November 10. What started out as a peaceful march with more than 4,000 people quickly turned violent. Portland police publicly declared a "riot" because of "extensive criminal and dangerous behavior," according to posts on the department's Twitter page. Hide Caption 10 of 30 Photos: Anti-Trump protests after election Demonstrators flood the 101 Freeway in Los Angeles on November 10. Hide Caption 11 of 30 Photos: Anti-Trump protests after election Police officers stand guard as they slowly clear Trump protesters from the 101 Freeway in Los Angeles on November 10. Hide Caption 12 of 30 Photos: Anti-Trump protests after election Demonstrators protest in Denver on November 10. Hide Caption 13 of 30 Photos: Anti-Trump protests after election Police officers look on as someone protests in Portland on November 10. Hide Caption 14 of 30 Photos: Anti-Trump protests after election Trump protesters march toward Interstate 94 in Minneapolis on November 10. Hide Caption 15 of 30 Photos: Anti-Trump protests after election Numerous cars at a Toyota dealership were smashed as people protested in Portland on November 10. Hide Caption 16 of 30 Photos: Anti-Trump protests after election Trump protesters chant outside the White House on November 10. Hide Caption 17 of 30 Photos: Anti-Trump protests after election Protesters set an effigy of Trump on fire outside Los Angeles City Hall on Wednesday, November 9. Hide Caption 18 of 30 Photos: Anti-Trump protests after election Demonstrators march down Second Avenue in Seattle on November 9. Hide Caption 19 of 30 Photos: Anti-Trump protests after election Police respond to a fire set by anti-Trump protesters in Oakland, California, on November 9. Police said some protesters threw Molotov cocktails, rocks and fireworks at officers. Hide Caption 20 of 30 Photos: Anti-Trump protests after election Protesters in Chicago display anti-Trump signs near the Trump International Hotel and Tower on November 9. Hide Caption 21 of 30 Photos: Anti-Trump protests after election Trump protesters take to the streets in Philadelphia on November 9. Hide Caption 22 of 30 Photos: Anti-Trump protests after election Thousands march down Fifth Avenue in New York on November 9. Authorities estimated as many as 5,000 people protested Trump's victory outside Trump Tower. Hide Caption 23 of 30 Photos: Anti-Trump protests after election Protesters rally against Trump in New York's Union Square on November 9. Hide Caption 24 of 30 Photos: Anti-Trump protests after election Demonstrators march past Radio City Music Hall in New York on November 9. Hide Caption 25 of 30 Photos: Anti-Trump protests after election People listen to speakers protesting Trump's election in Seattle on November 9. Hide Caption 26 of 30 Photos: Anti-Trump protests after election A woman argues with police officers during a protest in New York on November 9. Erin Michelle Threlfall, the woman pictured, told The Huffington Post she was attempting to intervene on behalf of a man she says the police were beating. Hide Caption 27 of 30 Photos: Anti-Trump protests after election Sasha Savenko, left, and Sydney Kane join thousands of protesters in Seattle on November 9. Hide Caption 28 of 30 Photos: Anti-Trump protests after election Crowds rally outside Trump Tower in New York on November 9. Hide Caption 29 of 30 Photos: Anti-Trump protests after election Charles Watkins speaks out at an anti-Trump protest in Denver on November 9. Hide Caption 30 of 30

At least 30 people were arrested and 11 citations were issued for vandalism, assaulting officers, unlawful assembly, failure to disperse and possession of a firearm.

Three police cars from nearby Pleasanton were damaged, officials said.

A few miles away at Berkeley High School, about 1,500 students walked out of classes Wednesday. In San Francisco, more than 1,000 students across the city walked out of the school and headed to the Civic Center to engage in a peaceful protest, according to a tweet from the San Francisco Unified School District.

"People are furious, not just at the results of the election but the rhetoric of Donald Trump," said Ahmed Kanna, an organizer for Social Alternative at Berkeley.

Chicago: 'We're taking many steps back'

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In Chicago, activists marched down Lake Shore Drive -- an eight-lane expressway along Lake Michigan -- toward the Windy City's Trump Tower.

"I still can't believe I have to protest for civil rights," one sign read.

CNN's Ryan Young, who saw a few thousand people there, said many chanted vulgarities toward the President-elect.

"As a nation we thought we had come so far, but it seems like we're taking many steps back," one woman said. "We want to come together to change that."

In Omaha, Nebraska, authorities deployed pepper balls on a crowd of more than 200 people protesting Trump's election after they defied police orders to stay out of the streets.

Los Angeles: Trump effigy torched

Dozens of high school and college students staged rallies near the USC and UCLA campuses.

Overnight, more than 1,000 protesters rallied outside Los Angeles City Hall, including many young Latinos.

More than 200 people gathered on steps of Los Angeles city hall protesting President-elect Donald Trump @KTLA pic.twitter.com/ZYJoMn3xVw — Kacey Montoya (@kaceymontoya) November 10, 2016

They chanted, "I will not live in fear," "Fight back, stand up" and "¡Si se puede!" (Spanish for "Yes, it can be done").

Protesters also set on fire a piñata depicting the head of the President-elect.

JUST WATCHED Donald Trump effigy burned by protesters. Replay More Videos ... MUST WATCH Donald Trump effigy burned by protesters. 01:56

Several protesters said they feared that family or friends might be deported once Trump takes office.

Brooklyn White, an 18-year-old who voted for Clinton, held a sign that said, "Hate won't win."

"We can't let it stop us," she said. "If he's the president, then fine. But if Donald Trump is going to be it, then he has to listen."

As many as 3,000 people joined Wednesday's demonstrations in the city, and 28 people were arrested for running into the 101 Freeway, said Los Angeles police spokeswoman Liliana Preciado. There was some property damage, but it's too early to know the exact extent, she said.

Mayor Eric Garcetti said in a statement, "I understand that the results of Tuesday's election are painful for many of us, and this kind of engagement can be a meaningful part of the healing we need after such a long and divisive campaign.

"But walking and throwing objects onto freeways is dangerous for pedestrians and drivers -- and it puts a heavy burden on people just trying make it home to their families or get to work safely."

Garcetti emphasized that the protests were largely peaceful, but said police would take quick action against those blocking traffic on interstates or vandalizing property, including news media vans.

"There is no place for the destruction of property, for the dangerous stopping of traffic," he said at a press conference Thursday. "Don't lose the message here. The message is that Los Angeles stands as the great hope."

Garcetti said 28 protesters have been arrested.

Washington: 'America has failed'

Meanwhile, protesters in Washington chanted, "No Trump, no KKK, no fascist USA," as they marched downtown to the Trump International Hotel.

Elsewhere in the nation's capital, an illuminated sign proclaimed that the US is "Better Than Bigotry."

Protesters from the group Avaaz display a "Better Than Bigotry" sign outside the White House.

"Everything that has been built up has been destroyed," protester Brian Barto told CNN affiliate WJLA-TV . "America has failed (minorities)."

Supporters: Trump an 'agent of change'

Trump supporters also rallied, showing their elation outside his current and future homes -- New York's Trump Tower and the White House.

Nicholas Elliot, a Georgetown University student, compared Trump's victory to the United Kingdom's Brexit vote to leave the European Union.

"I feel pretty good. A year-and-a-half process has ended, and it ended my way," the Texan told WJLA

J.D. Vance, author of the book "Hillbilly Elegy," said Trump supporters in middle America voted for him because so few people -- including Clinton or her supporters -- had paid attention to their plight.

"They see Trump as an agent of change and (an) agent of protest against folks who they feel have really failed in government," Vance said.

Now comes the hard part: finding middle ground, CNN's Marc Preston said.

"All that anger that has been contained outside of Washington, D.C., and New York that we don't see in middle America ... everyone's starting to see it," Preston said. "There is a lot of healing that has got to happen."