Police in riot gear battled hundreds of protesters with pepper spray and smoke bombs and arrested 130 people yesterday at the start of the Republican presidential convention.
Officers on horseback, motorcycles and bicycles chased a group of rock- and bottle-throwing protesters who broke off from a peaceful march of up to 10,000 people through downtown St Paul.
Protesters smashed shop windows, overturned garbage cans and vandalised police cars. Some pushed a flaming skip into a car with police in it, officers and witnesses said.
Police said 130 people had been arrested. The charges ranged from trespassing to property damage and assault, a spokeswoman said.
Demonstrators marched from the Minnesota state capitol to the heavily barricaded Xcel Center, where John McCain accepts the Republican presidential nomination later this week. Public safety officials put the crowd at 8,000 to 10,000.
Most protesters demanded an end to the Iraq war, although their causes ranged from increased rights for immigrants to changing US policy in Ethiopia. T-shirts backing Mr McCain's Democratic rival Barack Obama were common.
Some carried signs supporting politicians like Republican Ron Paul, a libertarian-leading Texas congressman and former McCain opponent, and Ralph Nader, a consumer activist running for president as an independent.
The march wound past bus stops where advertisements from the Democratic National Committee showed Republican President George W. Bush and McCain hugging with the slogan, "Does this look like change to you?"