An ATR 72-201 operated by Russian regional airline UTair crashed this morning shortly after taking off from Tyumen in Western Siberia, killing at least 31 of the 43 occupants, including the entire four-person crew. Flight 120 came down in a snow-covered field near the town of Korkovka at around 7:50 a.m. local time, minutes after taking off for a 400-mile flight to the oil town of Surgut. The 12 reported survivors remain in critical condition in a nearby hospital.

ATR originally delivered the 68-seat turboprop, registered as VP-BYZ and identified as Serial Number 332, from its Toulouse, France, production line in October 1992. UTair had operated the aircraft since August 2008.

The Russian Interstate Aviation Committee (IAC) will lead the investigation and serve as the official source of information, said ATR in a statement. According to international regulations, ATR will advise the French Bureau d'Enquêtes et Analyses (BEA), the safety investigation authority representing the state of the aircraft manufacturer.

Although ATR said the circumstances of the accident remain undetermined, local reports indicate that the crew tried to execute an emergency landing after a mechanical failure of some sort. Witnesses reportedly saw smoke emanating from at least one of the airplane’s engines just before it crashed.