Summary Shiveluch erupts in Russian far eastAsh shoots up 20 km into the skyVast ash cloud in Russian far eastAviation warning issuedResidents trudge through ash driftsVLADIVOSTOK, Russia, April 11 (Reuters) - One of Russia's most active volcanoes erupted on Tuesday shooting a vast cloud of ash far up into the sky and smothering villages in drifts of grey volcanic dust, triggering an aviation warning around Russia's far eastern Kamchatka Peninsula. The Shiveluch volcano erupted just after midnight reaching a crescendo about six hours later, spewing out a ash cloud over an area of 108,000 square kilometres, according to the Kamchatka Branch of the Russian Academy of Sciences' Geophysical Survey. "The ash reached 20 kilometres high, the ash cloud moved westwards and there was a very strong fall of ash on nearby villages," said Danila Chebrov, director of the Kamchatka branch of the Geophysical Survey. He said the volcano would probably calm now, but that further major ash clouds could not be excluded. Scientists posted pictures of the ash cloud billowing swiftly over the forests and rivers of the far east and of villages covered in ash.

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