There were eight known survivors, Russian media cited crises service authorities as saying.
Thirteen sightseers, including a youngster, and three team were ready when the Mi-8 smashed and sank in the Kuril Lake on the Kamchatka Peninsula.
Crises service rescuers and jumpers have been shipped off the space to look for those still unaccounted for.
The helicopter having a place with the Vityaz-Aero organization is supposedly lying at a profundity of 100 meters (330 feet) in the lake.
As per primer data, the airplane was on course from the town of Nikolayevka to the Kuril Lake and the Khodutka well of lava when it smashed, the crises service said.
The Mi-8 – a medium twin-turbine helicopter – was conveying vacationers from Moscow and St Petersburg, Russia’s news office RIA revealed.
The precipitous Kamchatka landmass – in excess of 6,000 km (3,730 miles) east of Moscow – is mainstream among travelers.