Russian officials say 48 people were killed when an Angara Airlines plane went down in a dense forest in the far-eastern Amur region.
The Antonov An-24 plane, carrying 42 passengers and six crew, had left Blagoveshchensk close to the Chinese border and vanished from radar screens as it approached Tynda airport, officials said.
A Russian civil aviation helicopter then spotted burning fuselage from the plane on a remote hillside about 16km (10 miles) from Tynda.
Amur’s regional governor Vasily Orlov said five children were among those on board and declared three days of mourning.
The remote, swampy nature of the area meant that rescuers took about an hour to reach the scene.
Preliminary inquiries are looking at either pilot error in poor weather conditions or technical malfunction, according to emergency officials.
The An-24 plane had been on the final leg of a route from Khabarovsk in the far south-east of Russia.
There was low cloud at the time of the crash, and the plane had already made a failed attempt to land at the airport, emergency services said. Radar contact was lost while the crew was preparing for a second approach, they added.
Angara Airlines is based in the Irkutsk region of Siberia and the crew all came from the Irkutsk region. A number of the passengers were working for Russian Railways in the far east.
The Antonov 24 plane was almost 50 years old and originally designed in Kyiv during the Soviet era, although this model has not been used in Ukraine for several years.
Officials said the plane had passed a recent technical inspection, but the civil aviation authority told news agencies it had been involved in four incidents since 2018.
Seven years ago its left wing had been damaged when the plane overran a runway and hit a lightning mast, Tass news agency said.
Other An-24 planes have been involved in fatal crashes, too.
An An-24RV veered off the runway as it landed at Nizhneangarsk Airport in July 2019. Two members of the flight crew were killed.
In 2011, another Angara An-24 crashed into the Ob river in Siberia, killing seven passengers.
After the 2011 crash, then-president Dmitry Medvedev said An-24 planes that were still in service in Russia should be grounded.
