People gather around a car as it is removed by a mobile crane in Tehran, Iran. The car was being driven by Iranian nuclear scientist Mostafa Ahmadi Roshan when it was targeted by a bomb Wednesday. Roshan was killed in the blast. Meghdad Madadi/AP hide caption

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Pakistani NGO workers protest at a rally on World AIDS Day in Peshawar in 2006. Tariq Mahmood/AFP/Getty Images hide caption

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A demonstrator throws a rock towards police during demonstrations in Tunis. Fred Dufour /AFP/Getty Images hide caption

itoggle caption Fred Dufour /AFP/Getty Images