Ukrainian strikes on Russian oil refineries may have disrupted more than 15 percent of Russian capacity, a NATO official said on April 4. Russia and Ukraine have both used drones to strike critical infrastructure, military installations, and troop concentrations. Kyiv’s forces have recently hit Russian refineries and energy facilities. "In terms of damage, the strikes have probably disrupted more than 10 percent of Russia's refinery capacity, maybe more than 15 percent,” the official told reporters on condition of anonymity. The official added that fewer and fewer of these types of Russian energy facilities are safe from potential strikes.