Observers say Putin is under pressure at home and abroad . U.S. officials say pro-Russian rebels were responsible for shooting down that plane , but they say they now believe it 's likely U.S. officials : Ukrainian troops moving closer to Russian border . Malaysia Airlines spokesman says missiles may have been fired from U.S. . The shootdown comes six days after Ukrainian security council Flight 17 was brought down .
Observers say Putin is under pressure at home and abroad . U.S. officials : Ukrainian troops moving closer to Russian border . Malaysia Airlines spokesman says missiles may have been fired from U.S. . The shootdown comes six days after Ukrainian security council Flight 17 was brought down .