A desperate rescue bid is underway to save the lives of 13 miners trapped 500ft underground at one of Russia's largest gold mines following a giant rock fall.A state of emergency was declared in Amur region after the collapse at the Pioneer mine which is owned by London-listed gold producer Petropavlovsk.Some 25 mountain rescuers of the Russian Emergency Situations Ministry's Neryungri paramilitary mountain rescue platoon were sent to the mine in Zeya district.
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