Mexico swears in president amid violent protests - Article Photos 45/54

Newly sworn-in Mexico's President Enrique Pena Nieto walks past a line of visiting dignitaries including U.S. Vice President Joe Biden, left, as he leaves the National Palace after delivering his inaugural speech in Mexico City, Saturday, Dec. 1, 2012. Protesters opposed to the new president clashed with tear gas-wielding police early Saturday morning outside the National Congress, where Pena Nieto took the oath of office. (AP Photo/Christian Palma)