Tsutomu Yamaguchi was a 29-year-old Mitsubishi ship designer from Nagasaki. In May 1945 he was sent to Hiroshima for about three months with two younger colleagues, Akira Iwanaga and Kuniyoshi Sato. They were due to go home on 7 August.

On the morning of 6 August he realised he had left his company seal (hanko) in his desk at the dormitory, went back for it, and was walking past sweet-potato fields near the tram terminus when he saw a B-29 and two small parachutes. He was about 3 km from the hypocentre. The left side of his face, his left arm and his neck were burned, and his left eardrum burst.

On 7 August he took a 1 p.m. evacuation train from Koi Station and reached Nagasaki the next morning. On 9 August, bandaged, he went back to work on the sixth floor of the shipyard office and was reporting to his section manager, who could not believe one bomb had destroyed a city, when the second bomb exploded at 11:02 a.m., again about 3 km away. "I thought the mushroom cloud had followed me from Hiroshima," he later said. Both of his colleagues survived Nagasaki too.

He stayed largely silent for decades. After his son died of cancer in 2005, he began speaking publicly, got his first passport at 90, and spoke at the UN in 2006. In March 2009 Nagasaki officials recorded his Hiroshima exposure on his survivor certificate, making him the first person officially recognised as a survivor of both bombings, though about 165 people are believed to have been in both cities. His compensation did not change. He died on 4 January 2010, aged 93.

Sources:

• Yamaguchi's memoir in English translation, "Double A-bomb Victim" (Nagasaki University repository): https://nagasaki-u.repo.nii.ac.jp/record/6738/files/kakyo13_87eng.pdf
• Japan Times (2009): https://japantimes.co.jp/news/2009/03/26/national/man-93-officially-declared-survivor-of-both-bombs
• AP via NBC News (2009): https://www.nbcnews.com/id/wbna29865222
• Kyodo via Hiroshima Peace Media Center (2010): https://www.hiroshimapeacemedia.jp/?p=14868
• History.com: https://www.history.com/articles/the-man-who-survived-two-atomic-bombs