An armed pro-Russian separatist gestures to reporters at the crash site of Malaysia Airlines Flight MH17, near the village of Hrabove (Grabovo), Donetsk region. The downing of the airliner with the loss of nearly 300 lives has sharply escalated the crisis in Ukraine, and may mark a pivotal moment in international efforts to resolve a situation in which separatists in the Russian-speaking east have been fighting government forces since protesters in Kiev forced out a pro-Moscow president and Russia annexed Crimea. Maxim Zmeyev/Reuters