Helicopter suffers extensive damage and blades snap off - but only one injury.
Rescue teams rush to help survivors among 22 passengers in Arctic.
A criminal case into possible negligence was opened after the Mi-8 crashed in a mountainous area of Khabarovsk region.
The helicopter carrying 17 people lurched on its side on takeoff, with 5 described as being in a 'grave' condition.
The Mi-8 training flight ‘exploded’ after slamming into a field with communications antennae at Khabarovsk Disaster Medicine Centre.
Mi-8 delivered Hannah McKeand and Canadian companion to remote island weather station but crashed soon after, as pair abandon North Pole attempt.
Intense search reveals no sign of Mil Mi-8 lost early Saturday with 12 people on board.
Three crashes in four days with total toll of 16.
The Mi-8 with 25 passengers and a crew of three on board crash landed some 45 km into a flight, said early reports.
A dozen passengers had a miraculous escape when a M1-8 helicopter fell on its side while landing.