On August 6, 1945, Tsutomu Yamaguchi was in Hiroshima on a business trip when the first atomic bomb detonated. Though injured, he returned to his hometown of Nagasaki. Three days later, while describing the blast to his boss, the second atomic bomb exploded. Yamaguchi survived both blasts and lived to the age of 93, becoming an official "double hibakusha" recognized by the Japanese government.
A Summer Assignment in Hiroshima
In the summer of 1945, Tsutomu Yamaguchi was a twenty-nine-year-old naval engineer and draftsman employed by Mitsubishi Heavy Industries. Based in his hometown of Nagasaki, he had been dispatched to Hiroshima in May for an extended three-month assignment to work on the design of a new oil tanker. As the summer drew to a close, Yamaguchi and his colleagues completed their engineering duties, packed their belongings, and prepared to return home to their families.
August 6, 1945, was intended to be Yamaguchi's final day in Hiroshima. Early that morning, he walked toward the city's railway station alongside two coworkers, Akira Iwanaga and Kuniyoshi Sato. While walking, Yamaguchi realized he had left his workplace identification stamp behind at the shipyard and turned back alone to retrieve it. This brief detour separated him from his companions and placed him out in the open on the city's docks just as the morning sky was pierced by the sound of an approaching aircraft.
Around 8:15 a.m., an American B-29 bomber, the Enola Gay, released the atomic bomb known as Little Boy over the center of Hiroshima. From a distance of roughly three kilometers from ground zero, Yamaguchi looked up and noticed the aircraft dropping what appeared to be small parachutes. Moments later, a blinding flash of light engulfed the sky, followed by a concussive shockwave that swept through the harbor area.
Surviving the First Blast
The force of the explosion lifted Yamaguchi off his feet, spun him through the air, and threw him into a nearby potato patch. The intense thermal radiation burned the left side of his upper torso and arms, while the immense acoustic shock ruptured both of his eardrums and left him temporarily blinded. After regaining his senses amid falling debris and smoke, he crawled toward an air raid shelter to escape the collapsing structures and spreading fires.
Yamaguchi spent the night in an improvised shelter along with other wounded workers, receiving rudimentary treatment for his burns and injuries. The following morning, on August 7, he set out across the devastated city toward the railway station. To reach the train lines that were still partially operational on the city's perimeter, he had to navigate a smoldering landscape and wade across a river choked with floating bodies and wreckage.
Against steep odds, Yamaguchi located his two colleagues, Iwanaga and Sato, who had also survived the blast with injuries. Together, the men boarded a train crowded with wounded refugees that made its way out of the ruined city and carried them south toward Nagasaki, unaware that the weapon they had just survived was unprecedented in human warfare.
Arrival in Nagasaki
Yamaguchi arrived in Nagasaki on August 8, heavily bandaged, running a fever, and suffering from acute pain. He reunited with his wife, Hisako, and their young son, Katsutoshi, both of whom were shocked by the extent of his injuries. Despite his severe burns, damaged hearing, and physical exhaustion, Yamaguchi reported to the Mitsubishi shipyard office the following morning to deliver his project debriefing and explain the situation in Hiroshima.
On the morning of August 9, Yamaguchi met with his company director and supervisor at the Nagasaki headquarters. In the meeting, he attempted to describe the sheer scale of the devastation he had witnessed, explaining that a single bomb had instantly flattened the entire city of Hiroshima. His superiors were incredulous, openly questioning how a single munition could destroy an entire industrial center and accusing him of exaggeration.
Just before 11:02 a.m., as the director was dismissing Yamaguchi's account as impossible, a brilliant white light flooded the office through the windows. The American B-29 bomber Bockscar had dropped Fat Man, a plutonium implosion-type weapon, over the northern Urakami Valley of Nagasaki.
The Second Detonation
The blast detonated roughly three kilometers from the Mitsubishi office where Yamaguchi was standing. The concussive wave blew out the reinforced windows, shattered interior walls, and threw Yamaguchi to the floor, tearing away the bandages that had been applied to his Hiroshima burns. Because the Mitsubishi offices were reinforced and situated within an industrial zone shielded by the city's hilly terrain, Yamaguchi once again avoided being killed outright by the thermal pulse and structural collapse.
Immediately after the explosion, Yamaguchi hurried through the chaotic streets to check on his family. His home had been reduced to rubble, but he discovered that his wife and infant son had survived with relatively minor injuries. Hisako had been out running an errand to purchase burn ointment for her husband when the air raid siren sounded, prompting her to take shelter in an underground tunnel with the child just before the bomb detonated.
In the days following the Nagasaki bombing, the cumulative effects of acute radiation exposure began to manifest. Yamaguchi suffered from severe radiation sickness, including uncontrollable vomiting, high fevers, the loss of all his hair, and the reopening of his severe burn wounds. For over a week, he hovered between life and death before his condition gradually stabilized under home care.
The Long Road to Official Recognition
In post-war Japan, individuals exposed to the atomic bombings were known as hibakusha, or 'explosion-affected people.' When the Japanese government established medical welfare programs and legal registries for survivors in the late 1950s, Yamaguchi registered as a survivor of the Nagasaki blast. Like many survivors, he avoided publicly discussing his experience in Hiroshima for decades due to social stigma, fear of discrimination against his children, and a desire to protect his family's privacy.
Survivors who were present during both detonations were colloquially referred to as 'nijū hibakusha' (double-survivors). While hundreds of individuals were believed to have traveled between the two targeted cities during those three days, very few pursued formal bureaucratic documentation acknowledging their presence at both detonations.
In the 2000s, as Yamaguchi entered his late eighties, he decided that his unique historical witness carried a responsibility. He formally applied to the Japanese government to amend his survivor certificate to reflect his presence in both Hiroshima and Nagasaki. In March 2009, the city government of Nagasaki officially certified his status, making Yamaguchi the first person legally recognized by the government of Japan as a double hibakusha.
Later Life and Anti-Nuclear Legacy
Following his recovery after the war, Yamaguchi worked as a translator for the Allied occupation forces, spent several years teaching, and eventually resumed his career as a naval engineer at Mitsubishi Heavy Industries. Though he suffered lifelong health issues linked to radiation exposure—including persistent hearing impairment in one ear and later bouts with cancer—he maintained an active lifestyle well into old age.
In his final years, Yamaguchi became an outspoken advocate for the complete abolition of nuclear weapons. In 2006, at the age of ninety, he traveled to the United States and addressed the United Nations General Assembly in New York, urging world leaders to eliminate atomic arsenals. He authored poetry and an autobiography detailing his ordeal, framing his survival as a mandate to warn future generations of the human reality of nuclear war.
Tsutomu Yamaguchi died on January 4, 2010, in Nagasaki at the age of ninety-three, following a battle with stomach cancer. His life remains an extraordinary chapter in modern history, standing as an enduring symbol of resilience and a primary eyewitness record of the dawn of the atomic age.
Key takeaways
•Tsutomu Yamaguchi was roughly three kilometers from the hypocenter of both atomic detonations: first on August 6, 1945, in Hiroshima, and again on August 9, 1945, in Nagasaki.
•He was in the middle of describing the Hiroshima explosion to his skeptical Mitsubishi supervisor in Nagasaki when the second bomb detonated.
•In March 2009, the Japanese government officially certified Yamaguchi as a 'double hibakusha,' formally recognizing him as a survivor of both atomic bombings.
•Yamaguchi lived to the age of 93, using his final years to address the United Nations and campaign for the total abolition of nuclear weapons.