Ukraine’s air force claimed Friday it shot down a Russian strategic bomber, but Moscow officials said the plane crashed in a sparsely populated area due to a malfunction after a combat mission. Previous Ukrainian claims of shooting down Russian warplanes during their more than two-year war have met with silence or denials from Moscow. Meanwhile, Russian missiles struck cities in the central Dnipro region of Ukraine, killing eight people, including a 14-year-old girl and 8-year-old boy, and injuring 28, local officials said.