Mikio Saiki, a 92-year-old atomic bomb survivor from Hiroshima, has begun sharing his harrowing experiences from nearly 79 years ago, a story he had kept to himself for decades. The catalyst for Saiki’s decision to speak out about the horrors of nuclear warfare is Russia’s invasion of Ukraine.

“People around the world don’t know the misery of nuclear weapons. We have an obligation to inform them,” he said. Saiki hopes that spreading the reality of the bombing will bring the world closer to the abolition of nuclear weapons and a world without war.

On the morning of Aug. 6, 1945, just before the end of World War II, Saiki, then 13 and a second-year student at Hiroshima Daiichi Junior High School (now Hiroshima Kokutaiji High School), experienced the bombing from his home about 2 kilometers east of the epicenter. He was about to run an errand for his mother when he saw a blinding light.