According to a representative of the regional emergency services, ammunition stored there began to detonate earlier on Wednesday on the premises of what is believed to be a former military facility in the Skopinsky district of the Ryazan Region.
"Preliminarily, there are explosions at the warehouses of the former military facility”, the source said.
Meanwhile, officials from the Russian Western Military District have stated that no one was injured in the explosion.
"Personnel and civilian staffers were evacuated. No one was injured ... There is no threat to the nearby settlements”, the Western Military District said in a statement.
According to the Western Military District, the grass caught fire not far from the Russian Defence Ministry's ammunition depot, and the fire then spread to the storage site due to gusts of wind.
The district added that three Mi-8 helicopters equipped with water discharge devices are on standby to fly to the area of the blaze.
"We are considering bringing a special Emergencies Ministry firefighting train to put out the fire," the district added.
So far, up to 10 pieces of special military equipment are involved, including two so-called firefighting tanks, two special armoured firefighting vehicles and five fire engines as well as 70 servicemen, says the Western Military District.
Meanwhile, more than ten villages are being evacuated because of the explosion, according to the Emergencies Ministry.
"We are evacuating residents from more than ten nearby settlements within the 5-kilometre [3-mile] radius," the ministry told Sputnik.
The ministry also mentioned that the federal highway R-22 Kaspiy had been blocked because of the incident.
"The traffic through the R-22 Kaspiy highway has been blocked," the ministry said.
The ministry also announced that it had sent 100 people and 26 pieces of equipment to deal with the fire.
The local emergency services told Sputnik that a bomb squad and robots from the Leader Center for High Risk Rescue Operations could be deployed to the Ryazan region for mine-clearing at the ammunition depot once the ammo stops exploding.