Workers in cities from coast to coast took the day off Monday to hit the streets and protest the Donald Trump administration for what organizers hoped would be the largest May Day demonstration in the U.S. in years.

The mass protest ― coordinated by labor, immigration and other progressive groups ― served as another early test of the grassroots momentum against the new White House and its right-wing policies. It came on the heels of a climate march that drew tens of thousands to Washington, D.C., on Saturday.

Backers of the May 1 protests saw the day as an ideal opportunity to challenge the Trump administration over its immigration crackdown. The president has promised to ramp up deportations of undocumented workers, strip federal funding from so-called sanctuary cities, and build a wall along the U.S. border with Mexico.

Zeferina Perez, a 59-year-old who came from Mexico two decades ago, said she wanted to show that American businesses cannot function without immigrant labor. She said it stung to see her community vilified on the national stage when immigrants were working hard for meager wages and often exploited to begin with.

“We need to demonstrate to everyone that immigrants are important to this country,” said Perez, who was passing out protest leaflets in D.C. ahead of Monday. “We’re willing to take any job that they give us. We only want to work and take care of our families.”

Quantina Pringle, a 34-year-old restaurant server, spoke at a workers’ rally in the Mount Pleasant neighborhood of D.C. Pringle called for an end to sexual harassment in the restaurant industry, and a raise in the tipped minimum wage. (Servers in D.C. are paid $2.77 per hour before tips.)

“I’m here for the people who have to balance their checkbooks off the attitudes of others,” said Pringle, who is a member of Restaurant Opportunities Center, a worker group that helped organize the May Day rallies.

Pringle was accompanied by her boss, Imar Hutchins, who owns the Florida Avenue Grill. Hutchins’ restaurant is typically closed on Mondays, but he said he had shut it down for the “day without immigrants” in February as a show of solidarity.

“I support my workers,” Hutchins said. “We try to make our restaurant the best place we can for our people.”

Police in Portland, Oregon, canceled a permit for a march there and said the demonstration had become a riot after self-described anarchists allegedly set fires and threw objects at cops, who responded by firing what TV-station KGW called “non-lethal weapons” at demonstrators. A police car was destroyed and windows were smashed. “Numerous people been arrested,” police said on Twitter.

In California, protesters faced off with local law enforcement on Monday while rallying against the immigration crackdown.

Credit: Justin Sullivan/Getty Images Protesters stand arm-in-arm to block the entrance to a U.S. Immigration and Customs Enforcement office in San Francisco.

In San Francisco, people formed a wall at the U.S. Immigration and Customs Enforcement building to block its entrance.

Los Angeles protesters began gathering before daylight Monday ahead of several marches taking place across the city.

Happening Now!

This is what democracy looks like.

Join us at MacArthur Park at 11 AM.#ResistLA pic.twitter.com/MyJS92r4EU — CHIRLA (@CHIRLA) May 1, 2017

Teachers in Philadelphia took sick days and protested over their lack of a contract, blocking traffic as they marched down North Broad Street. Students joined them, protesting outside a school during a break.

Cars honking as 100s of #phled teachers march down N Broad Street. "No contract, no peace," teachers chant. pic.twitter.com/L08F9nr4gE — Kristen Graham (@newskag) May 1, 2017

In downtown Denver, a crowd of more than 100 union members, community activists and others spent the morning marching in protest of Trump and to fight for better working conditions for all people, immigrants included.

“Remember, this is just the beginning,” Sharon Bridgeforth, board president of community organizing group Together Colorado, told protesters. “Our families are in jeopardy. Our families are hurting.”

“We’ll be back,” they called out to Bridgeforth.

Eva Martinez, representing Service Employees International Union local chapter 105, told HuffPost in Spanish that she came out to send a “message to Trump that we are together and we are strong and we’re going to fight.”

The crowd took a winding march through the city to deliver a letter to Molson Coors Brewing Co. headquarters. The document called on the beer giant to stop funding Trump, Sen. Cory Gardner (R-Colo.) and politicians “who endanger and attack our communities, including Latino communities, one of Coors’ biggest and fastest growing client bases.”

“You promote hate and fear, we don’t want to drink your beer,” people chanted.

Credit: Ryan Grenoble/HuffPost Protesters in Denver marched to the doorstep of a major beer company.

Credit: Ryan Grenoble/HuffPost Eva Martinez, second from right, rallied with other union members in Denver, as protesters chanted, "Si se puede!"

In New York City, workers picketed outside B&H Photo after the company announced earlier this year it would shut down its two warehouses in the city, cutting more than 300 jobs.

Later in the day, New Yorkers rallied at Union Square, including a large showing of immigrants and their children skipping work or school to protest.

Vicky Barrios, a social worker and organizer for immigrant rights group Movimiento Cosecha, said “this country would fall and collapse” without immigrants like her parents.

“I don’t think we should be scared on a daily basis about either being harassed, humiliated, harmed or deported,” Barrios told HuffPost. “I don’t think that’s how we’re suppose to live.”

Carolina Moreno/HuffPost Vicky Barrios, right, a social worker and organizer for immigrant rights group Movimiento Cosecha, pictured at a rally at ﻿﻿a rally at Union Square in New York City.

Victor Toro, 74, has been living illegally in New York since he escaped the dictatorship of Chilean Gen. Augusto Pinochet in the 1980s. He considers himself a “proud undocumented immigrant.”

“For me, Trump isn’t the problem,” said Toro, founder of La Peña, a cultural and political center in the Bronx. “The problem is the capitalist state that’s implanted here in the United States that’s sometimes led by Republicans and other times Democrats. Both are the same thing. The people have to open their eyes. When the Democrats were in power they expelled more than 2 million undocumented immigrants, and no one did anything against Obama. We want to create an autonomous movement.”

Boycott @BHPhotoVideo ! Don't cross the picket line! pic.twitter.com/bNzg0Dj8ln — NY Worker Center Fed (@NYWorkerFed) May 1, 2017

In Chicago, a historic union stronghold and sanctuary city, dozens of groups representing interests ranging from labor rights to immigration reform joined a midday protest. Hundreds of people packed into the city’s Union Park, itself a longtime rallying site for the U.S. labor movement.

“When it comes to our rights as workers, it doesn’t matter your racial, ethnic, religious status. These things cut across those lines,” said Abraham Diaz, of Arise Chicago, a group that advocates for labor-friendly local policy like paid sick leave and a living wage. “And they’re under attack in this administration.”

Miguel Mora of AFSCME 2854 said his group’s core message is that government must better serve the community — which includes veterans, disabled people, children and the elderly, as well as middle-class workers. Mora’s union has been fighting for a contract since June 2015. He said rhetoric from politicians like Trump and Illinois Gov. Bruce Rauner (R) is inconsistent with their anti-labor views.

“[They’re] attacking the working people,” Mora said. “The idea that we make a lot of money or too much money is not true. I’m a father, and I can’t put my kids through college. We can’t make it in this economy.”

Tony Johnston, president of the Cook County College Teachers Union, said his teachers were similarly fighting for a fair contract and were also standing in solidarity with immigrants rights on May Day.

“So many of our students are in that situation and they’re feeling vulnerable,” Johnston said of the new wave of policies in the Trump era.

Several businesses in different cities closed their doors to show their support for the May Day protests and immigrants’ rights.

in solidarity with our neighbors #teresamarket and #DayWithoutImmigrants free coffee on us for all strikers #immigrantswelcomehere pic.twitter.com/qJTtLgRES6 — Wildflower Pantry (@WFPBoston) May 1, 2017

The May Day holiday has radical roots in the American fight for an eight-hour workday, and it serves as an annual working-class celebration of labor in many foreign countries, including Mexico. The largest May Day demonstration in recent U.S. history occurred in 2006, when hundreds of thousands of immigrant workers went on strike to rally for immigrant rights.

As they laid the groundwork for this May Day, organizers had that massive protest in mind ― echoing other recent, anti-Trump demonstrations, like the massive women’s march that followed Inauguration Day.

“I think May 1 is the start of something, just as Jan. 21, with the women’s march, was the start of something,” said David Huerta, president of United Service Workers West, which is part of the Service Employees International Union. “We have to continue to voice our grievances with this administration and let them know there’s a resistance building. This isn’t just about immigrants or women. It’s about all of us who are being targeted.”

Although large-scale U.S. strikes are at a historic low in modern times, Trump’s election has kindled hopes on the left of a massive general strike to shut things down. February’s “day without immigrants” managed to shut down restaurants and other businesses in certain cities. March’s “day without a woman” brought thousands to Trump’s doors in Washington mid-week, many of them forgoing work for a Wednesday.

Nelson Lichtenstein, a labor historian at the University of California, Santa Barbara, said it remained to be seen whether the strikes have a legacy.

“We may be entering an era of political strikes, in which unions and other groups set a date and an agenda, but in which lots of unaffiliated people join in,” Lichtenstein said. “The question is: Can these strikes be given any sort of institutional backbone, any impact other than a one-time event that needs to be recreated from start each time?”

Unions like Huerta’s played a major role in May Day planning, advising workers on their rights if they wanted to strike and pressuring companies not to retaliate against anyone who takes part. Tech companies like Google and Facebook have agreed not to punish employees who are out for the day, and they’ve encouraged their contractors who employ low-wage janitors and food service workers ― many of them Latino immigrants ― to do the same.

Credit: Justin Sullivan/Getty Images Protesters in San Francisco denounced President Donald Trump's plan to build a wall on the U.S. border with Mexico.

In Washington, a local immigrant rights group called Many Languages One Voice was canvassing the downtown business area asking employers to close for the day. If they were unwilling to do that, the group wanted them to commit to allowing employees to miss work without reprisal. The group handed managers pledge sheets to sign, and doled out information about the protests to workers, telling them not to work or shop on Monday.

“We want folks to see that there’s a group on the ground that’s concerned about retaliation,” said Hannah Kane, an organizer with group. Kane said more than two dozen restaurants, hair salons and other mostly independent businesses had agreed to shutter for the day. Her group planned to accompany workers back to work on Tuesday if they were concerned about being punished.

There have been several short-lived protest strikes since Trump took office, including a temporary work stoppage by taxi drivers at JFK International Airport. That strike was a direct response to an executive order issued by Trump barring refugees from several Muslim-majority countries from entering the U.S. The “day without immigrants” in February closed restaurants and some schools in cities like Washington.

Perez said she hoped that May Day would one day become the working-class celebration in the U.S. that it is in her native Mexico.

“May Day is the worker’s day,” she said. “Here they don’t honor the work that immigrants do. We want people to respect us and our rights.”

KENA BETANCUR via Getty Images People attend a May day rally in Union Square on May 1, 2017 in New York.

Mike Segar / Reuters Demonstrators try to remove a person opposing their rally during a May Day protest in New York, U.S. May 1, 2017.

KENA BETANCUR via Getty Images People attend a May day rally in Union Square on May 1, 2017 in New York.

KENA BETANCUR via Getty Images Benny Zable, an activist from Australia, attends the May day rally in Union Square on May 1, 2017 in New York.

Mike Segar / Reuters A demonstrator rests among signs during a May Day protest in New York, U.S. May 1, 2017.

Mike Segar / Reuters Demonstrators gather during a May Day protest in New York, U.S. May 1, 2017.

FREDERIC J. BROWN via Getty Images Protesters march against President Donald Trump's immigration policy in Los Angeles, California on May 1, 2017, where tens of thousands are expected to take to the streets on May Day.

Chris D’Angelo contributed to this report. Dave Jamieson reported from Washington; Kate Abbey-Lambertz reported from Detroit; Ryan Grenoble reported from Denver; Carolina Moreno reported from New York; Kim Bellware reported from Chicago.