Kerry: Repercussions for Putin 'act of aggression'

Pro-Russian militants
Pro-Russian militants station themselves behind a row of shields near a local government building also guarded by heavily-armed troops on March 2, 2014 in Simferopol, Ukraine. The new government of Ukraine has appealed to the United Nations Security Council for help against growing Russian intervention in Crimea, where thousands of Russian troops reportedly arrived in recent days at Russian military bases there and also occupy key government and other installations. World leaders are scrambling to persuade Russian President Vladimir Putin to refrain from further escalation in Ukraine. Ukraine has put its armed forces on combat alert.
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