Some 500 people have been arrested as thousands of protesters, some of them purposely vomiting on public property, carried out their pledge to cause mayhem in downtown San Francisco to convey opposition to the U.S.-led attack on Iraq. KRON-TV reports roving bands of demonstrators linked themselves with metal chains and occupied intersections, while others sat stoically and then lined up in plastic handcuffs to be loaded into buses amid a backdrop of supporters chanting "This is what democracy looks like" and "The people have the power."