TEHRAN, Iran – Iran declared President Mahmoud Ahmadinejad the winner Saturday of an election that pitted the conservative establishment against candidate with broad backing from the country's youth. Riot police attacked opposition supporters, beating them with clubs and smashing cars.

A statement from Mousavi posted on his Web site condemned what he described as the "manipulation" of election results.

Demonstrators wearing the trademark green color of Mir Hossein Mousavi chanted slogans condemning the results that gave 62.6 percent of the vote to Ahmadinejad. Protesters set fire to tires outside the Interior Ministry in the most serious unrest in Tehran in a decade.