MAR DEL PLATA, Argentina (AFP) -- Hundreds of demonstrators clashed with Argentine riot police, targeted an American bank and looted shops as U.S. President George W. Bush and other leaders opened a summit nearby. Security forces fired tear gas but could not stop demonstrators hurling fire bombs into the offices of Boston Bank and smashing the windows of nearby stores.
Police said 64 people were arrested, while one young woman was seen being led away from the streets with blood pouring from a head wound.
The clashes erupted just 600 meters (yards) from the Hermitage Hotel in Mar del Plata where the 34 nation Summit of the Americas is being held.
Bush's motorcade avoided the troubles however. Tourists were seen snapping photographs of his vehicle as he drove from his hotel to the Hermitage for the start of talks.
More than 10,000 people had staged an anti-summit march earlier in the day and 40,000 attended a rally in a soccer stadium where Venezuela's President Hugo Chavez was among speakers opposing a U.S. free trade plan.
Later more than 300 radicals from extreme left wing groups, most with masks covering their faces, tried to break through the metal and concrete barriers set up as the initial cordon around the summit area.
They threw rocks at security forces. In return riot police on motorbikes fire back tear gas.
The protestors roamed through nearby streets, setting fire to the bank and ransacking three stores belonging to the Telefonica phone company.
About 30 attackers tore up the sidewalk and hurled the concrete through the windows of a Bank Boston branch. A branch of British-owned bank HSBC was also targeted and an office of Banco Galicia was set ablaze under a barrage of Molotov cocktails.
McDonald's and Burger King fast-food restaurants also had their windows smashed.
About 8,000 security forces had been deployed in the Atlantic sea resort in anticipation of unrest. Riot police in vehicles formed lines in front of metal barriers that ringed the security zone set up around the hotel. A dozen small armored vehicles were stationed along a main avenue nearby.
The violence came as thousands of Argentines staged strikes and took part in protests nationwide against the visit by Bush.
Schools, universities, hospitals, courts and other public sector staff joined the protests in about 200 towns and cities across Argentina.
Organizers said several hundred thousand people took part in the protests.
Argentine football hero Diego Maradona, Nobel Peace laureate Adolfo Perez Esquivel and the populist frontrunner in Bolivia's presidential race, Evo Morales, were also among the activists at the rallies in Mar del Plata.
There were also protests in other countries.
In neighboring Uruguay, hooded protestors rampaged through the historical heart of Montevideo, leaving six people injured, including three police officers, Uruguayan Interior Minister Jose Diaz said.
Fifteen people, including six women, were arrested in the anti-Bush, anti-capitalist violence in the capital, Diaz said.
Workers in the Bolivian town of Villazon staged a symbolic protest with Brazilian counterparts on a border bridge, organizers said.