Updated

An explosive detonated at a Russian military base in Chechnya, killing one official and injuring at least 13 more, Chechen law enforcement said Monday.

The blast occurred Sunday on the Khankala military base outside the capital Grozny, in a building used by prison guards, Chechnya's Interior Ministry said. One guard was killed and 18 others were injured.

The head of Russia's federal prison agency was quoted as saying that terrorism was not suspected in the blast. The force of the blast was equivalent to that of 2-3 pounds of TNT.

"Careless handling of ammunition or explosives is the most likely cause of the blast," Yury Kalinin was quoted by Interfax as saying. "Unfortunately, incidents involving fatalities do occur in places where large amounts of weapons and explosives are stored."

Large-scale fighting is rare in Chechnya, the site of two devastating wars pitting Russian forces against separatist rebels in the past 12 years, but rebel fighters continue to carry out small-scale, hit-and-run attacks. Violence has increasingly spilled over into neighboring regions of Russia's poor, troubled North Caucasus.

CountryWatch: Russia