At least 52 people have been killed after a bus caught fire in a remote part of Kazakhstan.

The Kazakh Interior Ministry said all of those killed were citizens of neighbouring Uzbekistan.

The bus was travelling along a road in Kazakhstan's north-western Aktau region that links the Russian city of Samara to Shymkent, a city in southern Kazakhstan close to the Uzbek border.

It was unclear in which direction the bus had been travelling, but the route is widely used to transport Uzbek migrant workers to and from Russia where they often take on work on building sites.

Only five people managed to escape the burning vehicle, the interior ministry's emergencies department said in a statement.

The ministry said the apparent accident had happened at 10.30am local time.