The wildfire broke out on Wednesday afternoon on the territory of a depot in the Ryazan region, reportedly containing some 75,000 tonnes of munitions. The flames spread to warehouses, setting off a large explosion.

Sixteen people were hospitalised with injuries but no one died, the health ministry said.

More than 650 servicemen, four Il-76 planes and three Mi-8 helicopters were taking part in the operation to put out the fire, the defence ministry said.

The planes dumped 126 tonnes of water on the fire, Interfax news agency quoted the defence ministry as saying.

A defence ministry spokeswoman declined to comment.

The emergency ministry said it had evacuated more than 2,300 residents living within a five-kilometre (three miles) radius of the fire.

Officials opened a criminal probe into potential breaches of rules on handling weapons.