Video published by state-owned broadcaster RT appeared to show bright sparks shooting out of a smouldering pile of rubble.

"The death toll from a fire at a fireworks factory in the Yaroslavl region has risen to 14, with one person injured," the state TASS news agency reported, citing Russia's emergency ministry.

The incident took place in the village of Kubrinsk, about 100 kilometres (62 miles) north of Moscow, TASS said.