More than 300 Occupy protesters have been arrested by the police, following the latest tension in downtown Oakland, California. Police fired tear gas at the massive group of demonstrators, who aimed at taking control of a convention center and the city hall. 　　According to the authorities, clashes erupted when close to 2,000 protesters marched the streets of Oakland on Saturday, followed by their attempt to turn the vacant Henry J. Kaiser Convention Center into their own protest headquarter. 　　Oakland police said protesters destroyed the construction equipment and tore down the fences of the Convention Center. In response to their violent act, which involved tossing metal pipes, bottles and burning flares, the authorities fired back with tear gas, smoke grenades and beanbag bullets to disperse the crowd. 　　The activists also broke into the Oakland City Hall and burn an American flag on the steps.