Putin sworn in as riot police clash with protesters
APTOPIX Russia Putin
Police detain a protester in downtown St. Petersburg, Russia at the same time Vladimir Putin's inauguration as president in Moscow Monday, May 7, 2012. Putin took the oath of office in a brief Kremlin ceremony on Monday, while on the streets outside thousands of helmeted riot police prevented hundreds of demonstrators from protesting his return to the presidency. (AP Photo/Dmitry Lovetsky)