The Russian Aerospace Forces used two BETAB-500 bunker buster bombs in Tuesday's airstrikes against ISIS targets in Syria, a spokesman for the Aerospace Forces in Syria said. "Today, Russian strike aircraft used two BETAB-500 bunker buster bombs weighing 500 kilograms [over 1,000 pounds] each against ISIL targets [in Syria]," Col. Igor Klimov told journalists in Syria. Klimov said the bombs were delivered by Russian Su-24 Fencer attack jets. "BETAB-500 bombs are used to destroy extremely protected and fortified underground bunkers, they are not dropped on cities," Klimov noted. A wide range of missiles and bombs equipped with advanced guidance systems are currently being used by Russia in its air campaign against terrorists in Syria. The concrete-piercing BETAB-500 bombs are equipped with a jet booster, which allows the bombs to completely destroy any underground installation.