Russian Mi-8 helicopter crashes in Siberia, killing 19
A Russian helicopter has crashed in north-western Siberia killing at least 19 people, officials say.
The Mi-8 helicopter carrying 22 people, mostly oil and gas workers, went down on Friday in the Yamalo-Nenetsky region.
President Vladimir Putin has expressed his condolences to relatives of the victims, according to his spokesman.
The helicopter "fell on its right side and the victims could not get out," a military spokesman said.
Three survivors were flown to the hospital but fog and poor visibility had hindered search and rescue operations, according to officials.
A criminal probe has been launched but investigators suspect the crash could have been caused by a violation of flight safety regulations, a mechanical problem or poor weather conditions.
The helicopter was flying from an oil and gas field in the Siberian region of Krasnoyarsk to the small settlement of Urengoi.
The region's governor Dmitry Kobylkin has announced a day of mourning, calling the crash a source of "great sorrow for all of us."