At least three people were injured and 13,000 evacuated after shells began to explode at an artillery depot in Udmurtia, a republic in the Volga area, shortly before midnight, a police source said on Friday.
"Three people were injured, they were taken to hospitals with injuries of varying degrees," the source said without elaborating on the condition of those injured.
Another source earlier said one person remained unaccounted for. The casualty and missing persons reports are currently being verified.
A total of 13,000 people were evacuated from six settlements close to the accident-hit facility.
At around 11:50 p.m. Moscow time [19:50 GMT] on Thursday shells began to explode in the Defense ministry's artillery depot near the village of Pugachevo. The facility belongs to the Defense Ministry's missile and artillery directorate.
Eyewitnesses said fragments of the detonating shells were spotted within the two-km (one-mile) radius.
The facility stores from 5,000 to 10,000 railway carriages with various ammunition. Some 18 storage facilities are thought to be on fire.
"Classic artillery shells are stored there, no self-propelled artillery," the source said.
A total of 200 personnel, 30 firefighting units and three firefighting trains were deployed to deal with the blaze and explosions that followed. The fourth train is to arrive from the neighboring republic of Tatarstan soon.
The Russian emergencies ministry said it would send two Il-76 firefighting aircraft, each able to carry 42 metric tons of water. They are to take off from Moscow's Ramenskoe airfield at between 4:00 and 5:00 a.m. Moscow time.
The accident forced the emergencies ministry to temporarily close the Yelabuga-Izhevsk zone of the M7 federal highway, connecting Moscow and Ufa, the capital of the Urals republic of Bashkortostan. The nearby railway link was also closed.
Udmurtia borders the republic of Bashkortostan, where fifty houses burned to the ground, and 160 people were left homeless as a result of powerful explosions at a local ammunition depot last week.
MOSCOW, June 3 (RIA Novosti)