SIBERIA: A Russian firefighting plane disappeared and went missing on Friday while extinguishing a forest blaze in Siberia, agencies reported. The Il-76 jet was operated by Russia’s Emergencies Ministry. It had dropped water on a forest fire in Kachugsky Region near the city of Irkutsk and was coming back to base when radio contact was lost. Sources quoted one official as saying the smoke was so thick and black that the visibility was “close to zero.” The cargo plane, modified to carry water, had a crew of up to 10 people aboard who are missing now, sources said. Investigators were quoted saying they do not know where the plane came down. Much of eastern Siberia is uninhabited wilderness. It was the plane’s second flight of the day to drop water on the blaze, agencies said, citing a source.