A Russian airliner carrying 143 people crashed and burst into flames near the Siberian city of Irkutsk, the Ministry of Emergency Situations said.
The Tu-154 plane belonging to the Vladivostokavia airline disappeared from radar screens about 9:10 p.m. Moscow time, news reports said.
The Interfax news agency said preliminary reports indicated all the 133 passengers and 10 crew aboard had died. The plane was en route from Yekaterinburg to Vladivostok, the major port on Russia's Pacific Coast.
The wreckage was discovered near the village of Budyonnovka, about 20 miles from Irkutsk, which is 2,600 miles east of Moscow.
Aviation Fell Into Decline
Following the collapse of the Soviet Union, civil aviation fell into a steep decline as hundreds of small airlines were spun off from the onetime monolithic Aeroflot.
Russia and other former Soviet republics were plagued by air crashes as aircraft maintenance and supervision deteriorated. But in recent years, the number of crashes appeared to have lessened.
The most recent major crash involving Russia was in October 2000, when an Il-18 transporting Russian soldiers crashed in Georgia, killing 83 people.
The three-engine Tu-154, first put into commercial service in 1972, is the workhorse of Russia's domestic airlines and widely used throughout the former Soviet Union and Eastern Europe, as well as in China.