A Russian passenger plane has gone missing over Indonesia, with at least 44 people onboard.
Indonesian authorities say it may have been hijacked or crashed into a mountain, according to Russian news agency RIA Novosti.
Radio and telephone contact have been lost, Russia Today reported.
The Sukhoi Superjet 100 was carrying out a demonstration flight over a mountainous area south of Jakarta.
It disappeared from radar screens at an altitude of 6,200 feet, shortly after the pilot requested permission to descend to 6,000 feet, RIA said.
The airplane was due to return to Jakarta’s Halim Perdanakusuma Airport 50 minutes after take-off, according to the Associated Press – but it has not been seen since.
Of those onboard, eight are Russians and 36 are from other countries. Most of them are from airlines considering buying the SSJ 100, according to RT.
Indonesia's national search and rescue agency has dispatched a team to the area.
"We are still looking for it and we are uncertain whether it crashed," spokesman Gagah Prakoso told Agence France Presse.
RT cites Indonesian air traffic officials as saying the search operation is being hampered by bad weather and approaching nightfall.
The plane had enough fuel for four hours' flight, according to the BBC.
The medium-haul aircraft had already carried out two demonstration flights earlier in the day, RIA said. It was on a tour of six Asian countries designed to show off its capacities to potential buyers.
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