TOKYO—A 93-year-old Japanese man has become the first person certified as a survivor of both U.S. atomic bombings at the end of World War II, officials said Tuesday. Tsutomu Yamaguchi had already been a certified "hibakusha," or radiation survivor, of the Aug. 9, 1945, atomic bombing in Nagasaki, but has now been confirmed as surviving the attack on Hiroshima three days earlier as well, city officials said. Yamaguchi was in Hiroshima on a business trip on Aug. 6, 1945, when a U.S. B-29 dropped an atomic bomb on the city. He suffered serious burns to his upper body and spent...