Fifty-two people have been killed after a bus they were travelling in caught fire in Kazakhstan's north western Aktau region.
Only five passengers managed to escape the burning vehicle, the country's interior ministry said. They are being treated for injuries.
An emergency services official told Russian state news agency RIA Novosti the bus was travelling from Uzbekistan to Russia.
The bus is believed to have been carrying Uzbek citizens along the Samara-Shymkent route, according to initial reports.
The route, which is about 2200km long, is frequently used by Uzbek migrant labourers travelling to construction sites in Russia.
A photograph posted online from the site showed the bus completely burnt out. Video footage also posted on the internet showed it positioned diagonally across a two-lane freeway in the middle of a snow-covered steppe, in flames and emitting heavy black smoke.
Uzbekistan's foreign ministry said in a statement its embassy staff were en route to the area, roughly midway between the Russian border and the Aral Sea.
Last October, another Kazakh-operated bus carrying over 50 Uzbeks was hit by a train in Russia after getting stuck on the tracks - 17 people died in that accident.