The fire at the Electrotsink metallurgy plant in Vladikavkaz in Russia's south broke out overnight to Sunday and continues to spread, the Russian Emergencies Ministry's press service said.
"The localization of the fire on the territory of the Electrotsink plant has been cancelled, the fire spread to 1,000 square meters," TASS cited the press service as saying.
It was earlier reported that the fire started in the electrolyte workshop and spread to 650 square meters, but was later localized. The workshop roof and walls partially collapsed.
One firefighter died and two more were injured in the fire. No employees of the plant were injured in the fire.