“The bodies of the dead are most likely at the bottom of Kurilskoe lake,” Interfax news agency quoted a health source as saying.
Divers were shown on state television at the lake in heavy fog. They were unable to dive down to the wreckage of the helicopter because it was too deep, Kamchatka’s governor said.
The thick fog may have caused the pilot to land on the surface of the water thinking it was land, the TASS news agency cited a police source as saying.
The Kamchatka peninsula is popular among tourists for its skiing, ハイキング, surfing and volcanoes. It is more than 6,000 キロメートル (3,700 マイル) east of Moscow and about 2,000 キロメートル (1,250 マイル) west of Alaska.
The helicopter was operated by Vityaz-Aero company and had 13 passengers and three crew, the local emergency service said.
Russian aviation safety standards have improved in recent years but accidents, especially involving aging planes and helicopters, are not uncommon.
7月に, すべて 28 people on board of Antonov An-26 twin-engined turboprop died in a crash in Kamchatka.