The Occupy D.C. campaign, largely peaceful since its launch two months ago, turned confrontational Sunday when police detained 31 protesters during a tense day-long standoff in McPherson Square. It was the first case of mass arrests at the group’s base camp in Washington, and the clash resembled those between police and Occupy protesters in other cities across the country.

The day began with a seemingly minor dispute over a 15-foot-tall wood shelter that protesters put up Saturday night in the park’s grassy southwest corner. But it soon escalated into a noisy downtown disruption — and a psychological turning point in the protests — after a group of demonstrators defied repeated orders by the U.S. Park Police to dismantle and abandon the half-built shed.

During the day, officers arrested 15 demonstrators and charged them with crossing a police line, Park Police spokesman Sgt. David Schlosser said. Shortly after nightfall, police moved in and detained the protesters who had remained inside the open shed all day, and 16 people were charged with disobeying a lawful police order. One of them also was charged with resisting arrest, indecent exposure and urinating in public.

Six people clung to the roof of the shed, but police were able to remove all of them by 8:35 p.m. and later dismantled the shelter.

There were no reports of injuries.

The Occupy D.C. movement took over a public park in the center of downtown amid a national and worldwide protest that has landed in most major American cities. Ranging from a few dozen to more than 100 protesters, the Washington group has railed against large corporations and banks and has rallied on behalf of the “99 percent” of the country they think has been oppressed by the wealthy few.

In view of the White House and in the middle of influential K Street, the protest has drawn much interest but little controversy during its stay. The impromptu building, however, changed things Sunday.

Occupy D.C. participants said Sunday that the structure’s only purpose was to provide a warm gathering place for protesters as winter weather sets in and that it had been designed by volunteer architects to comply with federal park regulations, which require any structure to be temporary and easy to move. It was built on stilts with no foundation.

Police officials — who have allowed the tent city to remain in a public park — insisted that the building was illegal because it appeared to be a permanent structure and the group had not obtained a permit for it. Whatever the original purpose of the building, it quickly became a lightning rod.

Police at first gave protesters a midmorning deadline to take down the structure, then relented and allowed about 20 people to remain inside. But they surrounded the site with a cordon of more than 50 Park Police officers, including a half-dozen on horseback.

For hours, protesters climbed onto the shed’s rafters and milled on the ground beneath, shouting slogans about justice and equality while police watched in silence. Periodically, shoving or shouting matches erupted along the security perimeter. Police generally stood back, but they did wrestle individual demonstrators to the ground and led them off in handcuffs toward police vans.

“Our message today is that the public space in America belongs to the people,” said Rob Wohl, 23, a protester from Arizona who remained inside the shelter hours after Park Police officials ordered the occupants to leave or risk arrest. Denouncing lenders that made profits while foreclosing on homeowners, Wohl said, “Let the world know that the police are arresting people who put up a structure, not who took one away.”

As night fell, rumors of imminent evictions swept the tent colony, and a few Occupy D.C. campers began packing up to leave. Six members of a Buddhist community in Poolesville held a prayer vigil and burned incense in the hope of a peaceful outcome.

About 6 p.m., Ann Wilcox, an attorney for Occupy D.C. at the scene, said police had determined that the shed was dangerous and issued the first of three warnings by megaphone, ordering the protesters to leave or face arrest. Instead, demonstrators started chanting, “Occupy Wall Street, Occupy K Street, occupy everywhere and never give it back.”

Two of the protesters on the shed’s roof jumped from the rafters into a moonbounce-like inflated cushion that had been set up by police. But the other four hung on until police went up in the bucket of a cherrypicker, which was parked at the open side of the structure to dislodge them.

Police put them, one by one, in a safety harness, plucking three of them from the rafters as the crowd cheered and chanted. It took about 15 minutes for police to remove the final protester, who had wrapped his legs around the building’s wood frame. Police tied a rope around him and dragged him onto a ladder.

The day-long confrontation was the first serious incident for Occupy D.C. since the birth of the movement, which has led to controversial happenings in several cities — including New York, Oakland, Boston and London. The most notable one occurred at the University of California at Davis, where police shot pepper spray at unarmed protesters, injuring several of them. The incident was caught on video and caused nationwide outrage.

District authorities had maintained a good relationship with the city’s Occupy movement and had largely taken a hands-off approach.

Until Sunday, there had been only a few scattered arrests in connection with Occupy D.C., and none at McPherson Square. Last month, about a dozen protesters were arrested after occupying a vacant school nearby. Six others were arrested after a traffic accident during a protest near the Walter E. Washington Convention Center, and D.C. Police Chief Cathy L. Lanier said protesters had become “increasingly confrontational and violent.”

Although the shelter was constructed under cover of night and created a mood of Alamo-like defiance, Occupy demonstrators said it was not planned to provoke authorities. But the structure created a flash point nonetheless.

The demonstrators repeatedly chanted, “This is a peaceful protest,” but several shouted a stream of profanities, magnified by crowd choruses, against the police. Michael Patterson, 21, who described himself as a war veteran from Alaska, loudly taunted officers just inches from their faces. He was eventually grabbed, forced to the ground and dragged to a waiting police van, struggling and yelling.

By the time police removed the last person from the building, Patterson, who said he was charged with crossing a police line, and other protesters who had been arrested earlier in the day had returned to the park. Patterson said the protesters made a statement that they “are not the normal protest group.”

“We are not just going to march for two or three hours,” he said. “We are here to stay ’cause the system needs to change.”

Aside from individual scuffles and arrests, however, police were generally restrained.

In keeping with the fluid, heterogenous character of the Occupy movement, the skeletal shed with U.S. and D.C. flags flying above it swiftly came to symbolize just about anything the protesters chose. Some said it brought attention to the plight of the homeless, while others used the high-profile moment to raise issues from air pollution to factory farming to corporate excess.

A 70-year-old man with a bushy gray beard, who gave his name as “Bear,” said he had been living in a tent in McPherson Square for more than a year, but was delighted when the Occupy group moved in around him. “I’m proud and happy to be here today. I’m defending my home, too,” he said.

Staff writers Michael Bolden, Tim Craig, Allison Klein, Michael Rosenwald and Teresa Tomassoni contributed to this report.


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