Russia's Defense Ministry said on Monday that explosions at a storage facility for gunpowder charges prompted the evacuation of 6,000 residents in the town of Achinsk, as well as towns and villages within a 20-kilometer (12.4-mile) radius.
Authorities declared a state of emergency in the Krasnoyarsk region.
Unverified videos posted on social media showed powerful explosions sending plumes of black smoke high into the sky.
Air traffic was suspended within 30 kilometers of the military site.
Krasnoyarsk governor Alexander Uss said that between five and eight people may have been injured.
"There is no threat to their lives," he added in televised comments.
Authorities planned to evacuate a further 11,000 people, broadcaster Russia 24 reported.
Rusal, the world's largest aluminum producer outside China, suspended operations at its Achinsk alumina plant and evacuated all but essential staff to ensure their safety, it said.
The plant is Russia's largest producer of alumina, a raw material which is smelted into aluminum.
Around a dozen accidents have happened in explosives factories across Russia since 2014, according to the TASS news agency.
kw/msh (AP, AFP)