"Explosions at gunpowder depots in the Rezhevsky District of the Sverdlovsk Region have been reported," the official said.
Preliminary information suggests that the buildings caught fire from a forest blaze, the official added.
Local authorities said they started evacuating the residents of Pervomaiskii village that lies close to the blaze. An emergency situation regime was declared in the Rezhevsky district, municipal head Ivan Kartashov said.
There are no casualties as a result of the fire at the warehouses, the regional office of the Russian Emergencies Ministry, citing preliminary data.
Later on Saturday, the office specified that the fire burnt down two warehouses.
"According to operational information, thanks to coordinated actions of fire and rescue units it was possible to prevent the fire from spreading to three storage buildings. As of now, the fire destroyed two warehouses totaling 960 square meters [10,333 square feet]. Firefighters continue to take all measures to contain the fire as soon as possible," the statement said.
Firefighting efforts in the village of Pervomaiskii continue, the statement added. According to local authorities, one firefighter was injured and was taken to the hospital.
A total of 400 local residents, including eight children, have been evacuated to temporary shelters, local authorities said on Telegram.