A Mi-8 helicopter crashed in Russia's Krasnoyarsk region on Thursday, killing 15 people onboard.
Russia's Emergency Situation Ministry confirmed there were altogether 25 people, including three crew members and 22 passengers, onboard.
The 10 people that survived have been hospitalized, Oksana Gorbunova, spokeswoman for the West Siberian Transport Prosecutor's Office was quoted as saying by the Interfax news agency.
The helicopter, en route to an oilfield in the region, crashed near the airport of Igarka and was found lying on its side on the right bank of the Yenisey River, a statement of Russia's Investigative Committee said.
It was unknown yet what had caused the accident. Interfax quoted an unnamed source from emergency services as saying that it could have been resulted from a technical malfunction.
(Updated)