Yesterday, thousands of New Yorkers poured into Union Square to protest the acquittal of George Zimmerman in the killing of 17-year-old Trayvon Martin.

We spoke to some of those who showed up in the afternoon, and you can find out what brought them there by clicking through the slideshow above. For many, the chants of “No justice, no peace!” and “The system is guilty, it freed George Zimmerman!” continued into the night and then into the wee hours during a march from the East Village to the Bronx.

About 12 to 20 people were arrested in Manhattan during the course of the evening, the police said.

During a 6pm rally, the crowd was perhaps 1,500 to 2,000 strong. Among those whose stories of injustice were amplified by a bullhorn and by the “people’s mic” was an elderly black woman who said that Trayvon Martin reminded her of her own son. Her voice faltering, she said she’d “lost him to the NYPD.”

Justice For Trayvon Martin, Union Square: Crowd listening to Kevin Powell

The crowd listens to speaker Kevin Powell. (Photos: Scott Lynch)

After a while the crowd was frothed and overflowing the park; traffic on 14th Street was at a standstill. Another protester at the bullhorn called for a march. The idea caught on and the crowd poured down Broadway, a chain of people with arms linked keeping the growing number of police cars and paddy wagons at bay. After winding through the East Village, the demonstrators — chanting, “Whose streets? Our streets!” — turned north at First Avenue and continued uptown.

The crowd seemed to go stronger as it cut westward across Gramercy and the Flatiron District while cars honked to show support. A young woman waved a sign that read “EMMETT TILL 1955 TRAYVON MARTIN 2013,” and another woman passed out Skittles, the candy Trayvon Martin was carrying home from the convenience store when he was shot. A half-dozen American flags hung from a building on 33rd Street, waving comically in the wind, as the crowd moved toward 8th Avenue.

About now is when the decision was made to march on Times Square. The rally — which must have been several thousand larger than when it began, and felt larger still — moved on Times Square, chanting, “Outta the stores, into the streets!” It was a chant directed primarily at the legions of tourists going about their touristy time in New York City. Several tour buses were stopped in the road, their upper decks jammed with people taking pictures.

Justice For Trayvon Martin, Union Square: Crowd

(Photos: Scott Lynch)

The crowd packed into Times Square and the people’s mic was used again to determine the next move. There was some fear that the group would be surrounded by the NYPD (dozens of police cars and scores of officers on foot, with bundles of plastic cuffs strapped to their belts, encircled the area), and so the protesters organized a sit-in, to the merciful relief of some. It had been three hours and thirty blocks.

There were more speeches about racial injustice, the broken criminal justice system, white privilege, and ones simply lamenting the fact that a boy was dead. One girl, in a sort of peroration of the entire evening, shouted, “We took Times Square!” which elicited vociferous cheers.

By 10 p.m. most of that fervor had dissipated as a few hundred protesters continued north, for Harlem and the Bronx, where the protests lasted into the morning. Those who’d been there from the beginning had marched at least six hours and 130 city blocks.

Officers in riot gear started making arrests on the Upper East Side; the first two were at 79th Street and Second Avenue. This morning, a police spokesperson said the exact number of those facing charges “consistent with disorderly conduct” had yet to be determined.