A Japanese man who survived the bombing of Hiroshima to become a prominent anti-nuclear campaigner has died at the age of 96. Sunao Tsuboi, then a 20-year-old student, narrowly escaped death when an American B-29 dropped an atomic bomb on the Japanese city on Aug. 6, 1945. Some 140,000 Japanese were killed in the blast but, despite being severely burnt and heavily irradiated, Tsuboi clung to life—a life he subsequently dedicated to ridding the world of nuclear arms. Tsuboi was the co-chair of a national organization representing hibakusha, assurvivors of the attacks on Hiroshima and Nagasaki are known. In 2016, he was introduced to Barack Obama when he became the first U.S. president to visit Hiroshima.