WASHINGTON, DC - MAY 01: A young protester holds his sign high as Casa in Action, and Service Employee International Union 32BJ hold a rally in Lafayette park after marching to "denounce Trump's anti-immigrant policies on May 01, 2017 in Washington, DC. (Photo by Bill O'Leary/The Washington Post) (Bill O'Leary/The Washington Post)

Don Juan Restaurant shut down. So did Haydee’s restaurant. And so did Pupuseria San Miguel. Customers yanked on the door handle of Ercilia’s restaurant, hoping for just-fried pupusas and freshly brewed coffee. Instead, they found themselves staring at locked doors.

“Closed to support general strike,” the signs said in English and in Spanish. “We support our workers today & every day.”

Dozens of businesses in Maryland, Virginia and the District shut down Monday, and thousands of protesters marched through the nation’s capital in sweltering heat to rally against President Trump’s immigration policies in front of the White House.

Some said the turnout was lower than expected, but others pointed out that they marshaled support for immigrants and workers on a weekday, and soon after massive marches for science and the climate.

“This is not the last rally,” said Alma Couverthie, organizing director of Casa, an organization in Maryland, Virginia and Pennsylvania that led the largest march to the White House. “There’s going to be many of these and then after this we’re going to go back to work. We’re going to call the Congress people. We’re going to lobby. We’re going to march again until what we need to have in this country happens.”

Ercillia's restaurant in Mount Pleasant was closed Monday as a May Day expression of solidarity with immigrants workers. (Maria Sacchetti /The Washington Post)

Demonstrators gathered at different points in the city — in the historic Latino neighborhood of Mount Pleasant, at Malcolm X Park and in Dupont Circle — and shut down streets as they marched toward the White House singing folk songs and waving signs and flags. Signs said, “Deport Trump,” and “This Swamp Fights Back,” a nod to the president’s pledge to “drain the swamp” in Washington.

Along the march routes, workers who could not take the day off stopped and waved or filmed with their phones. A cook at Chipotle smiled from the door. Around the corner, construction workers stopped hammering.

At DC Variedades on Mount Pleasant Street, owner Delmy Garcia said she tried to close for the day but customers begged her to open so they could buy cell phones and pay their telephone bills. She said it is difficult for small businesses to close, even for a day, even when the nation’s immigrant communities are fearful of the border and deportation crackdown that Trump promised.

“I support immigrants. But closing businesses is really tough,” Garcia said, as she stood behind a glass counter. “If you close, you always pay for it.”

The march to the White House was part of a nationwide mobilization Monday to support immigrant rights through rallies, teach-ins and vigils, said Kica Matos, a spokeswoman for the Fair Immigration Reform Movement, which coordinated the national effort.

Organizers planned 149 strikes, rallies, marches and other events in 125 cities and 35 states, in addition to one overseas in Vienna.

Facebook, Google and the City of Seattle all told employees they could take the day off to participate.

People take part in a May Day rally and march in Washington, DC, 01 May 2017. Labor Day or May Day is observed all over the world to celebrate the economic and social achievements of workers and fight for laborers rights. (Michael Reynolds/EPA)

In Portland, Ore., the marches turned violent, and more than two dozen people were arressted.

In Washington, the marches closed streets in Mount Pleasant, Dupont Circle and elsewhere as early as midday. Dozens of police officers escorted the demonstrators on what appeared to be a peaceful protest. No arrests were reported.

Organizers said people protested in different ways: Some stayed home from work or school. Others took to the streets.

Karen Rice, 25, a doctoral student in philosophy at Georgetown University, said she missed work to join the protest.

“I’m on strike,” said Rice, who normally would have been working as a teaching assistant at that hour. “I’m an American citizen, so I need to be here and support others.”

She held aloft a sign showing a phone number that workers can call if they are fired for striking. Many Languages One Voice, an organization in the District, planned to escort demonstrators back to work Tuesday to urge employers not to fire them for the one-day strike, said Executive Director Sapna Pandya, who marched Monday.

By 3 p.m., the crowd streaming from Dupont Circle ballooned and poured into the streets for the mile-long march to the White House. With a police escort and herded by volunteers wearing traffic vests, the demonstrators shut down the stretch of downtown Washington traffic for an hour. Some wore white Casa in Action T-shirts distributed by the immigration advocacy group, while others, organized by unions, donned orange traffic vests and purple Service Employees International Union shirts.

American flags outnumbered protest signs at the center of the throng of people. Their chants included “Si Se Puede,” “No Papers, No Fear” and “Donald Trump Has Got to Go.”

A few handwritten signs said, “Immigrants Made America Great.”

Around 4 p.m., the group gathered at the White House for a massive rally. Guards peered from the top of the White House and dozens of police officers waited nearby as members of Congress, community leaders and immigrants demanded respect for immigrant workers.

“Whether it’s the White House or the Empire State Building, we built this country,” said Rep. Anthony G. Brown (D-Md.), as the crowd cheered.

Fenit Nirappil contributed to this report.