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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Bosom Pals, an iconic sculpture by Russian artist Vasily Konovalenko. Denver Museum of Nature and Science hide caption

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Former U.S. and Russian diplomats gather at RIA Novosti in Moscow on Tuesday. From left: former Russian or Soviet ambassadors to the U.S. Vladimir Lukin, Alexander Bessmertnykh and Viktor Komplektov; Sergei Rogov, director of the Institute of USA and Canada; and former U.S. ambassadors to Russia James Collins, Jack Matlock, Thomas Pickering and John Beyrle. Alexander Zemlianichenko/AP hide caption

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