At least 52 people have died after a bus caught fire in Kazakhstan, emergency officials said.

The Emergencies Ministry said the incident happened in the northern Aktobe region of the former Soviet nation in Central Asia.

The ministry said five of 57 people in the bus survived the fire, and are being treated for injuries.

The ministry said some of the victims were citizens of neighbouring Uzbekistan.

The cause of the fire was not immediately clear, but investigators suspect it was triggered by a short circuit.