Washington ? Dancing in a conga line and shouting calls for peace, demonstrators on Sunday pressed as close to the White House grounds as they could get to demand that President Bush back off Iraq. Police swiftly arrested those who breached barricades.

A crowd of about 1,000 rallied in view of the Executive Mansion, capping a weekend of demonstrations that featured a huge and peaceful rally Saturday and protests around the world.

At one point Sunday, protesters flooded into a street to block traffic; police pushed and dragged them back. In the scuffle, an older woman who was part of the demonstration was pushed over. Ambulance officials said she was one of two people transported to hospitals with minor injuries suffered during the demonstrations. The hospital where the woman was taken declined to release information on her injuries, saying it had not received permission from the patient to do so.

Protesters were not sure they could stop America from going to war. But Dunya Cope, 18, a Georgetown University freshman, wanted history to note that they tried.

“Historically, it’s important to show that there was such an outcry, that people just didn’t go along with it,” she said.

On a weekend of remembrance for Martin Luther King Jr., many invoked the civil rights leader’s legacy of nonviolent resistance. Said Heather Williams, 30, of Alexandria, Va.: “We still have a dream.”

Close to 500 protesters assembled first near the Justice Department and FBI headquarters to denounce “racist witch hunts” by U.S. authorities following the 9-11 attacks.

During a mile-long march in the cold, that crowd met another of a similar size, waiting by Lafayette Park across Pennsylvania Avenue from the White House. That set off a surge of enthusiasm and some began running toward, and over, chest-high barricades blocking the park boundaries.

U.S. Park Police stand guard as other officers behind them arrest protesters who jumped the fence at Lafayette Park, across the street from the White House. More than a dozen arrests were made Sunday during the rally.

Police forced them face down on snowy grass, bound their wrists with plastic handcuffs and made 16 arrests. They were processed on misdemeanor charges and released.

Despite that, the mood was largely festive. Scores formed a conga line that snaked along the packed section of H Street — on the other side of the park from the White House — that was set aside for the protest. Others tied themselves together with yarn.

But organizers had pledged nonviolent civil disobedience, making the tone tenser than Saturday, when tens of thousands rallied and only a few people were taken into custody. About 100 tried to block traffic and were moved forcefully by police.

Bush was at Camp David, Md., for the weekend. Protesters wanted to get as close as possible to the White House to protest his Iraq policy.

Condoleezza Rice, Bush’s national security adviser, welcomed the protests as an expression of American freedoms.

“And it contrasts so greatly with the situation that people in Iraq find themselves in, where your tongue can be ripped out for criticizing the regime,” she said on NBC’s “Meet the Press.”