The death toll from the catastrophic flood inside Russia's biggest hydroelectric power station has risen to 17 but 58 people were still missing, officials said on Thursday.
"As a result of the disaster 17 people have died and at the current moment the fate of 58 workers of the plant is unknown," a spokesman for the emergencies ministry's rescue operation said, quoted by news agencies.
Some 2,000 people were working on the rescue effort at the Sayano-Shushenskaya plant in the southern Siberia.
Work started early Thursday to drain the turbine hall which was flooded by a massive surge of water in Monday's disaster, Emergencies Minister Sergei Shoigu was quoted as saying.
There has been mounting anger amongst relatives of the missing that the authorities have yet to give further information on the fate of the dozens still unaccounted for, over three days after the tragedy occurred.