Demonstrators against the war picked up where they left off Thursday, marching, holding vigils and continuing a wave of blockades at intersections, buildings and roads that triggered more rounds of arrests coast to coast.

Here at the scene of the largest protests in the country, where 1,400 people were arrested Thursday over an 18-hour period for blocking streets and buildings and paralyzing the financial district, the protests today were smaller, quieter and less disruptive. About 100 demonstrators blocked the entrance to Bechtel Corp. -- to protest, they said, the corporation's bid for contracts in rebuilding a postwar Iraq -- and were promptly arrested. About 250 protesters marched for hours through downtown before some broke away and tried to block a street, but they were quickly dispersed by police. The protests continued throughout the day and evening, and a total of 220 people had been arrested in the city by nightfall. But police expected the numbers to go up.

Demonstrators said they planned more disruptions in coming days."We will sustain this for many days," said Jamie Hurlbut, an office worker who joined protesters blocking downtown San Francisco traffic today after eight hours in police custody. "This is just the start. I literally went to sleep and came back out to hit the streets again," he said.

There were peaceful rallies against the war in dozens of cities, from Irvine, Calif., to Albany, N.Y., and also small rallies in support of the war and the Bush administration in a number of cities. In Ohio, several hundred people rallying to support the troops brought shaving cream, toothpaste and other supplies for the soldiers. In return, Gov. Bob Taft (R), distributed 1,000 red, white and blue ribbons. In Pittsburgh, downtown Market Square was the scene of simultaneous rallies for and against the war, and no incidents were reported.

In Boston, 200 people rallied at City Hall Plaza, culminating a five-week peace march. There were stepped-up demonstrations in other cities, especially at federal courthouses and buildings. In Baltimore, 30 of 70 people who dropped to the ground outside the federal courthouse in a "die-in" were arrested this morning. In Minneapolis, 200 people, some carrying a giant coffin, staged a "die-in" at the federal courthouse. In Los Angeles, about 1,000 antiwar demonstrators rallied outside the West Los Angeles Federal Building, briefly clashing with police and forcing the closure of one of the city's busiest intersections at rush hour. At least 14 were arrested. In Sacramento, 30 people were arrested for blocking that city's federal building.

Other protests at federal buildings were held in Seattle; Hartford, Conn.; and New York, where protesters descended on the offices of Democratic Sens. Hillary Rodham Clinton and Charles E. Schumer of New York. In San Francisco, police blocked hundreds from entering the offices of Sen. Dianne Feinstein (D-Calif.).

Throughout the country, including Washington, D.C., protesters taking part in one of the largest national campaigns of civil disobedience since the Vietnam War also focused on blocking traffic. In Santa Rosa, Calif., 50 people were arrested for blocking a road. In East Lansing, Mich., about 100 protesters, including some who were chained together, blocked a main road near Michigan State University. Police arrested 14 people. In Lawrence, Kan., a man dressed as Uncle Sam stopped traffic as he dribbled red liquid on mock victims lying in the street.

Most of the civil disobedience protests, which led to about 420 arrests nationwide today, were calm and peaceful.

Here in San Francisco, protest organizers had vowed to shut down the city for the second day in a row. But after so many arrests Thursday -- the most in one day in this city of protests -- San Francisco seemed to be nursing a hangover early in the day. On Thursday night, small pockets of demonstrators calling themselves anarchists or members of "the black bloc" scuffled with police. Tonight, as several hundred demonstrators and police gathered near City Hall, the mood was intense.

San Francisco Mayor Willie L. Brown blamed outside agitators for the disruptions and grumbled about the costs of policing protests, which cost the city $450,000 in police overtime Thursday alone.

More rallies and protests were planned in major cities on Saturday, including national rallies in New York and San Francisco.

An antiwar demonstrator, right, confronts a Young Republicans rally in support of the Iraq war in Fresno, Calif. Mike Johnson, a Vietnam veteran, tries to hold back a pro-war demonstrator.A protester wears fake scars and bruises as she takes part in a demonstration against the war in Iraq, in New York's Times Square, one of many demonstrations across the country.