The blasts at the hydropower plant in Russia's North Caucasus republic of Kabardino-Balkaria were equivalent to more than 10 kg of TNT (22 lbs) altogether, a source from the local law enforcement authorities said on Thursday.
The attack saw a group of up to four gunmen burst into Kabardino-Balkaria's Baksan Hydropower Plant early on Wednesday and shoot dead two security guards. Then they detonated four explosive devices. The resulting blaze covered an area of 250 sq meters.
The attackers were apparently well-trained militants, the source said. The Russian Federal Security Service has said the gang's leader had been identified.
The head of RusHydro's plant in the North Caucasus, Ali Sattaev, said two hydro units were damaged as a result of the blasts. However, a RusHydro spokesman said energy supplies to Kabardino-Balkaria would not be affected by the attack.
Some experts say the attack may be a "rehearsal" that could be followed by other similar attacks.
MOSCOW, July 22 (RIA Novosti)
