Six soldiers were killed and 12 injured on Tuesday in a blast at an anti-aircraft missile facility in the Astrakhan region, the fourth such incident since April, the Defense Ministry said.
The blast took place outdoors at the Ashuluk facility, the ministry said in a statement that did not report the condition of the injured or the cause of the blast.
A spokesman for military prosecutors in the Southern Military District said investigators are "not ruling out any version, but the violation of safety rules during destruction of old ammunition remains a priority one," RIA-Novosti .
A source in the Astrakhan police also told the news agency that the ammunition had been mishandled, but did not elaborate.
The Lifenews.ru tabloid two conflicting sources, both unidentified, that said the soldiers were preparing obsolete missiles for destruction or that the rockets were new and intended for test launches.
All those injured were shellshocked and hospitalized in serious condition, the tabloid said. A military spokesman RIA-Novosti that they were being evacuated by helicopter.
Ashuluk is located six kilometers from the barracks and 60 kilometers from the nearest settlement, which ensured that no civilians were hurt in the explosion, news reports said.
In June, some 28,000 people were temporarily displaced by a blast at a Urals arms depot near the village of Pugachyovo in Udmurtia, allegedly caused by a discarded cigarette. A conscript was killed, 95 people were injured, and more than 2,000 sought psychological help during the incident.
In May, 12 people sustained injuries in a similar explosion at an arms depot in Bashkortostan, also blamed on the mishandling of old ammo. Forty buildings, including 14 residential ones, were destroyed in the blaze that followed.
In April, a blast at an old arms depot in the Lipetsk region village of Kadinka, where old gunpowder was being destroyed, killed four.
President Dmitry Medvedev threatened to "strip epaulets" from those responsible for the Udmurtia blast, but no discharges have been reported for military top brass.