Protesters fill Bay Area streets for May Day demonstrations

Immigrant and workers rights advocates, fueled by anger over President Trump’s policies, staged raucous May Day protests Monday that attracted thousands of people in cities in the Bay Area and around the nation.

While May Day usually inspires throngs of loud voices, Monday’s crowds were especially invigorated by the Trump administration’s priorities, particularly against undocumented immigrants.

“It’s our duty to unite together,” said Yadira Sanchez, 26, one of hundreds of demonstrators who blocked the U.S. Immigration and Customs Enforcement headquarters in San Francisco’s Financial District. “There’s growing momentum. People are angry and upset.”

After circling the streets around the ICE building, the protesters marched down Clay Street to Justin Herman Plaza. By noon, the crowd had swollen to several thousand. Protesters began marching west, down the middle of Market Street. Traffic stalled and police held back cars on side streets.

Shoulder to shoulder at the front of the throng were San Francisco Mayor Ed Lee and San Francisco supervisors Jane Kim, Katy Tang and Ahsha Safai, directly behind a banner proclaiming “Unidos Somos la Fuerza” (”Together We Are Strong”).

Veronica Gonzalez (left) and Miriam Cuevas (right) cheer as they protest immigration rights and fair pay outside of the U.S. Citizen and Immigration Services building on Sansome Street in San Francisco, California, on Monday, May 1, 2017. less Veronica Gonzalez (left) and Miriam Cuevas (right) cheer as they protest immigration rights and fair pay outside of the U.S. Citizen and Immigration Services building on Sansome Street in San Francisco, ... more Photo: Gabrielle Lurie, The Chronicle Buy photo Photo: Gabrielle Lurie, The Chronicle Image 1 of / 107 Caption Close Protesters fill Bay Area streets for May Day demonstrations 1 / 107 Back to Gallery

At Civic Center Plaza, the crowd lay down on the scant patches of green, gulping water and slurping frozen treats, while speakers took to a small stage and Latino rappers did their thing.

“Today is a labor day and an immigration day,” said Yemeni expatriate Ahmed Abosayd, a vice president of the Service Employees International Union local chapter.

Abosayd, whose son, Mustafa, was detained at San Francisco International Airport in the opening hours of the first version of Trump’s travel ban in February, urged the crowd to “give a message to Donald Trump: No ban, no wall.”

In past years, protesters seemed to represent many causes. This year, labor unions, immigrant advocates, teachers and environmentalists coalesced around a single anti-Trump message.

In Oakland, a few dozen protesters gathered at the Alameda County Administration building. Four demonstrators were arrested after chaining themselves to the front of the building.

Demonstrators called on the county Board of Supervisors to “rein in the sheriff” and stop the agency’s cooperation with ICE.

“By connecting the fight for immigrants with the fight against police militarization, people in Oakland are standing together,” said Mohamed Shehk, a 28-year-old organizer with the Oakland Sin Fronteras activist group. “People are galvanized — they see a need to organize and resist.”

In all, about 100 demonstrators gathered in the plaza in front of the administration building a couple blocks from Lake Merritt, some with babies, dogs and bicycles in tow. It was a diverse coalition that included Asians for Black Lives, Critical Resistance and Third World Resistance.

“We’re just out here to demand the Board of Supervisors stop their reliance on military policing — specifically with Urban Shield,” said Woods Ervin, 34, of Oakland, referring to the police training program founded by Alameda County Sheriff Gregory Ahern in 2007.

Thousands of protesters rallied in downtown San Jose, where some buses were rerouted and many businesses were closed. Mayor Sam Liccardo welcomed the marchers and vowed to “celebrate our community as a welcoming and inclusive place for our immigrant neighbors ... in contrast to the rhetoric emanating from Washington.”

Other protests were being organized by the California Teachers Association. The events were expected to put a strain on substitute teacher rolls.

By early in the evening, thousands of people were still marching in Oakland, having made it deep into the city's Fruitvale neighborhood before switching course to the north, marching toward Lake Merritt.

Among the masses was 68-year-old Roy Wilson, an Oakland resident since 1998 and the executive director of Oakland's Martin Luther King Jr. Freedom Center, a group that builds civic engagement amongst local middle and high schoolers.

Wilson was opposed to a number of things: Trump in general, cutting back environmental regulations and the like.

"We the people don't understand, don't care, or don't know what it means," he said, referring to America's status as the most powerful country in the world and how the president is changing things, changing fast.

Dropping sweat and hoisting a sign with three students, Wilson, asked if he was tired after marching since early afternoon, didn't skip a beat.

"Tired?" he said. "I'm feeling great."

Evan Sernoffsky, Filipa Ioannou and Steve Rubenstein are San Francisco Chronicle staff writers. Email: esernoffsky@sfchronicle.com, fioannou@sfchronicle.com, srubenstein@sfchronicle.com