Five young children and two adults were killed when a fire ripped through a two-storey residential building in the central Russian city of Rostov early Saturday, authorities said.

The youngest child to have died was 15 months old and the oldest six, a spokeswoman for the emergency’s ministry told AFP.

Three more people were hospitalised with various injuries, said Sergei Shokin, head of the Rostov municipal district.

Rostov is located some 200 kilometres (124 miles) northeast of the capital Moscow.

Officials did not immediately say what caused the fire but confirmed investigators were working at the scene.

The Investigative Committee said it had opened a criminal probe.