On Aug. 9, 1945, when the U.S. military dropped an atomic bomb on Nagasaki, Mitsuko Suyama, then 8, was playing with her sister, three years her senior. They were at a community center in the village of Koga, now part of Nagasaki, about 11 kilometers from the hypocenter.

“Get down,” shouted an older student, as a bright flash was followed by a roaring sound. The bomb exploded in the sky above the district of Matsuyama in the city of Nagasaki. Suyama opened her eyes and stepped outside: Burned debris and ashes, including banknotes, fell from the dark sky and her hands turned black as she grabbed them.

“If it gets in my mouth, I'll die," she thought to herself immediately, and tried to run away. But the black, thick “rain” started falling again. Amid the downpour that lasted for about five minutes, her sister pulled her as they rushed to their house 500 meters away. Suyama's white shirt was stained black, and cinders flew into the house as they entered the building.