SAO PAULO, Brazil -- Police clashed yesterday with students, environmentalists and leftist Brazilians protesting against a visit by President George W. Bush and his push for an ethanol energy alliance with Latin America's largest country.

Riot police fired tear gas at protesters and beat them with batons in Sao Paulo after more than 6,000 people held a largely peaceful march, sending hundreds of demonstrators fleeing and ducking into businesses to avoid the gas.

To visit Colombia

Authorities did not immediately report any injuries but Brazilian news media said at least six people were hurt after marching three kilometres through the financial heart of South America's largest city just hours before Bush was scheduled to arrive.

Police and anti-Bush protesters also clashed in Colombia, where Bush is scheduled to visit Sunday as part of his five-country tour of Latin America.

At Bogota's National University, 200 masked students clashed with 300 anti-riot police and shouted "Out Bush!" Police fired tear gas and the students hurled back rocks and small homemade explosives called "potato bombs" -- aluminum foil wrapped around gunpowder. There were no immediate reports of injuries or arrests.

In the southern Brazilian city Porto Alegre, more than 500 people yelled: "Get Out, Imperialist!" as they marched to a Citigroup Inc. bank branch and burned an effigy of Bush.

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