As Sochi, Russia, prepares to host the 2014 Olympic Games, workers walk past piles of dirt at the construction site of Fisht Stadium and Olympic Park on May 20. Artur Lebedev/ITAR-TASS/Landov hide caption

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A column of Russia's T-90 tanks rumbles over the cobblestones in Moscow's Red Square on May 9 during the country's Victory Day parade celebrating the anniversary of its costly victory over Nazi Germany in World War II. Yuri Kadobnov/AFP/Getty Images hide caption

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French actor Gerard Depardieu (right) chats with Chechen leader Ramzan Kadyrov shortly after his arrival in Chechnya's capital, Grozny, on Feb. 24. Musa Sadulayev/AP hide caption

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Investigators work at the site of a bombing in the Dagestan capital, Makhachkala, last year. The blasts near a police post killed at least 15 people. The southern Russian republic has seen persistent violence. AFP/Getty Images hide caption

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In this image taken from a cellphone video, the father of the Boston bombing suspects, Anzor Tsarnaev, talks to the media about his sons, in his home in Makhachkala, the Dagestani capital, on Friday. AP hide caption

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