NOVO-OGARYOVO, August 25 (RIA Novosti) - Rebuilding an oil depository destroyed by fire in north Siberia's Khanty-Mansi Autonomous Area will cost some 1.5 billion rubles ($48 million), the head of Russian pipeline operator Transneft said on Tuesday.

Nikolai Tokarev told journalists after a meeting with Prime Minister Vladimir Putin that the fire caused damage estimated at 145 million rubles ($4.6 million), but reconstructing the facility will require "1.5 billion rubles if it is considered feasible to completely rebuild the reservoirs."

The fire at the Konda facility started on Saturday when lightening struck an oil reservoir containing 20,000 cubic meters of oil before spreading to two other reservoirs.

Over 350 firefighters were involved in tackling the fire which was brought under control on Monday. Four firefighters were killed and another four injured in the operation.

The Khanty-Mansi Autonomous Area lowered its flag to half mast in memory of those who died in the fire with August 25 declared a day of mourning.