Anti-government protesters rest on their collapsed tent following clashes with the police as they called for the resignation of President Ali Abdullah Saleh in Sanaa, Yemen.
Ahmad Gharabli/AFP/Getty Images
About a week after the opening ceremony of the 1996 Summer Games in Atlanta, a bomb went off in Centennial Park. Two died and more than 100 were injured, but the games went on.
Pedro Ugarte/AFP/Getty Images
Migrants ride on top of a northern bound train toward the U.S.-Mexico border in Oaxaca, southern Mexico, in March. Migrants crossing Mexico to get to the U.S. have increasingly become targets of criminal gangs who kidnap them to obtain ransom money.