Police repulsed anarchists, gay activists and other protesters across Midtown Manhattan on Tuesday, arresting 560 people as they tried to block traffic and many as they simply walked on sidewalks. The action prevented what was to have been a major show of civil disobedience outside Madison Square Garden on the second night of the Republican convention.

About 200 arrests came as the War Resisters League, a pacifist group, marched about 1,000 strong from Ground Zero toward Madison Square Garden. And police arrested about 150 people who were standing on sidewalks about four blocks from the Garden and refused police orders to disperse. Scores of riot police surrounded Union Square late Tuesday as about 1,000 protesters gathered on the periphery, then dispersed without incident.

Confrontations sometimes turned physical, as undercover police officers tackled bands of anarchists marching down the middle of the city's broadest avenues.

"It appears that some of the hard-core groups are still trying to get to the Garden," said Paul Browne, deputy police commissioner for public information. "But we're not letting them through."

Most of the protests were carried out by a loosely organized anarchists' collective calling itself A31, for August 31, with a goal of calling attention to what Raquel Lavina, a Bay Area organizer, termed "Bush's foreign terror and war at home." Protesters assembled outside office buildings housing military contractors, hotels where Republican delegates were staying and the Midtown offices of Fox News.

Police Commissioner Raymond W. Kelly commended officers' restraint in the face of what he called "relentless provocation."

But New York Civil Liberties Union associate legal director Chris Dunn accused police of improperly arresting the 200 War Resisters League protesters after agreeing to let them walk north on a sidewalk from Ground Zero to the area around Madison Square Garden. Dunn said the protesters never left the sidewalk, but police moved in anyway after they had walked one block, surrounding them with orange netting and arresting them.

About 800 other members of the group dispersed rather than be arrested.

"When you are the cops, you can apparently arrest people anywhere you want. They've got the guns," Dunn said.

Police also arrested dozens of people walking toward the Garden near Union Square and late Tuesday arrested 150 walking on 35th Street, about four blocks from the Garden. "I was just walking down the street. I was just following everybody," a man who identified himself as Michael Costanzo of New Jersey called out to a reporter. Later, Michael Collins, a high-ranking police official, told reporters in the area: "These people were told to disperse. They were given a warning. If they don't disperse, then they get arrested."

In an unrelated incident, Yale student Thomas Frampton, 21, was arrested after entering a restricted area near Vice President Cheney's booth at the convention. Frampton, a Sidwell Friends graduate and former housing activist in the District, came within 10 feet of Cheney and shouted antiwar and anti-Bush statements. Authorities said Cheney was never in danger. Frampton was charged with assaulting federal officers and impeding the operation of the Secret Service.

Throughout the day, small groups of protesters showed up at sites designated on the Web site of A31 as protest targets: Fox News, the Westin Hotel housing the Missouri delegation and buildings housing the Carlyle Group, Rand Corp. and Lockheed Martin Corp. But at most of these places, there were more police officers and reporters than protesters. Police arrested small groups of protesters trying to disrupt traffic in the financial district or loitering on subway platforms uptown, Kelly said.

Hundreds of demonstrators rallied outside the Fox News studios in Midtown Manhattan, yelling, "Shut the Fox up," their voices echoing off the windowed skyscrapers.

Fox employees streamed into the courtyard to watch as protesters hurled their criticism at a television network they see as an unwavering supporter of the Bush administration.

"It's propaganda," said Deborah Ben-Elizer, 34, a New Yorker wearing glasses with swirled lenses to represent what she called a zombie public that has fallen under the spell of Fox. "They're in bed with [the Bush administration]. They're sleeping together," she said.

Police built a double barricade four blocks from Madison Square Garden in all directions, and at one point, Fox reporter John Deutzman was interviewing protesters there when several realized he was from Fox and surrounded him, yelling, "Liar! Liar!" About 50 protesters joined in until police opened the barricade and gave Deutzman a haven inside.

Also Tuesday, Riverside Church in Harlem hosted a gathering of 3,000 New Yorkers to "call attention to the real moral, social and economic issues of this election," the Rev. James A. Forbes said. Afterward, churches throughout the city rang their bells "to demonstrate that faith does not belong to one party," as Forbes put it.

Staff writer Dale Russakoff contributed to this report.

On the second day of the Republican National Convention, Marlene Rocha reads a magazine as George Lee, Ovay Henkel and Max protest deaths in wars in Iraq, Afghanistan and elsewhere. Members of the small, autonomous protest group sat silently on a subway train going uptown as police followed them. They were arrested for disorderly conduct when they tried to change trains. New York Police Commissioner Raymond W. Kelly said there were 260 arrests Tuesday, for a total of about 800 since protests related to the convention began Thursday.Police arrest protesters gathered at the New York Public Library. Throughout the day, small groups of protesters showed up at the offices of military contractors, Fox News, hotels housing Republican delegates and other spots.A New York police officer uses his nightstick to drive back a crowd of protesters and members of the media during a protest in front of the New York Public Library. The group planned to continue marching on to Madison Square Garden, the convention site.