Protesters attacked delegates, smashed windows, punctured car tires and threw bottles Monday, a violent counterpoint to an otherwise peaceful anti-war march at the Republican National Convention. Police arrested at least 56 people.

The protesters, many clad in black and identifying themselves to reporters as anarchists, wrought havoc away from the antiwar march by damaging property and setting at least one fire. Most of the violence was in pockets near downtown, several blocks from Xcel Energy Center where the convention was taking place.

Police estimates of the crowd shifted several times during the event, ranging from 2,000 to 10,000. The crowd was clearly in the thousands. Late Monday afternoon, long after the antiwar marchers had dispersed, police requested and got 150 Minnesota National Guard soldiers to help control splinter groups near downtown.

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