Washington (CNN) -- Top American officials harshly criticized Russia on Friday for its continued support of pro-Russian rebels in Ukraine following the downing of a Malaysia Airlines jetliner. President Barack Obama said Friday that Russian President Vladimir Putin has the "most control" over the situation in eastern Ukraine as intelligence indicates that rebels most likely shot down Flight 17 from an area they control with a surface-to-air missile. Nearly 300 people were killed in Thursday's disaster, including one American. Obama said the rebels' sophisticated weaponry and training needed to shoot down aircraft "is coming from Russia" and said the United States could ratchet up sanctions on Russia if it continues to support the rebels.
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U.S. intelligence suggests pro-Russian separatists shot down Malaysia Airlines Flight 17
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President Obama said Putin has the "most control" over the situation in eastern Ukraine
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Sen. John McCain and Rep. Peter King said outright that Putin is "responsible"
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"Russia can end this war. Russia must end this war," the U.S. Ambassador to the U.N. said
@placeholder officials rebutted even the suggestion of Russian involvement and instead blamed Ukraine for creating a volatile environment in eastern Ukraine.
Russian officials rebutted even the suggestion of Russian involvement and instead blamed Ukraine for creating a volatile environment in eastern @placeholder.