By Pavel Polityuk and Polina Nikolskaya KYIV/DONETSK (Reuters) - Russian President Vladimir Putin authorised a military operation in eastern Ukraine on Thursday in what could be the start of war in Europe over Russia's demands for an end to NATO's eastward expansion. Shortly after Putin spoke, a Reuters witness heard the sound of what appeared to be explosions in the distance from the capital, Kyiv. Explosions also rocked the breakaway eastern Ukrainian city of Donetsk and civilian aircraft were warned away as the United States said a major attack by Russia on its neighbour was imminent. In co...
