VLADIVOSTOK, Russia, Oct. 22 (Xinhua) — Twenty-one people died and three others were rescued after an MI-8 helicopter crash-landed in Russian Siberia's Yamal Peninsula due to poor weather conditions.

The two black boxes of the ill-fated helicopter have been found by rescuers on the peninsula in northwestern Yamalo-Nenets Autonomous Region.

One of the injured has been sent to a hospital in nearby Urengoy village for treatment.

"Both black boxes have been found - a flight data recorder and a voice recorder. After investigative procedures, they will be sent for decryption," Russia's RIA Novosti news agency quoted a source from Russia's Federal Agency for Air Transport as saying.

There were 22 passengers and three crew members aboard when the helicopter made the crash landing at 06:57 p.m. (1557 GMT) on Friday 80 km northwest of Urengoy. One of the three seriously injured survivors called the emergency department with a mobile phone.

"Arrived rescuers have found three people in serious condition when entered the ruined helicopter," the Russian news agency TASS reported.

Local emergency department has dispatched the first search and rescue team of 140 people, who took 20 pieces of equipment with them to the site of the accident.

The helicopter was flying from Suzunskoe oilfield in Krasnoyarsk region to the Urengoy village when the accident happened.