On August 6, 1945, he was in Hiroshima, preparing to return home from a business trip when the American B-29 bomber, the Enola Gay, dropped an atomic bomb on the city. Mr Yamaguchi lived, while 140,000 other people who were in the city that morning died, some in an agonising instant, others many months later.

Burned and barely able to comprehend what had happened - only that he had witnessed a bomb unlike any used before - Mr Yamaguchi spent a fitful night in an air raid shelter before returning home the following day.

That home, 290 kilometres to the west, was Nagasaki. His arrival came the day before it was devastated by a second US atomic bomb on August 9.

In a barely conceivable course of events, he had twice been at nuclear ground zero; and both times he had lived. More than 70,000 other residents of Nagasaki were not so lucky.

Now the 93-year-old has became the first and only known survivor of both attacks to win official recognition from Japanese authorities.

Other survivors died prematurely from cancer and liver disease caused by their exposure to radiation, but Mr Yamaguchi remains in relatively good health apart from near-deafness in one ear and complaints that his legs are "growing weak".

According to a newspaper interview Mr Yamaguchi gave on the 60th anniversary of the end of the Pacific war, he had spent the conflict designing oil tankers for Mitsubishi Heavy Industries.

After a three-month stint at the firm's yards in Hiroshima, Mr Yamaguchi was preparing to return to Nagasaki when he heard the Enola Gay circling above.

Within seconds he had been knocked to his feet by the force of the blast as "Little Boy" detonated 580 metres above central Hiroshima. As he stumbled to the train station the next day, Mr Yamaguchi witnessed the destruction and carnage left by the bomber's 13-kiloton payload.

He reported for work in Nagasaki, like Hiroshima an important industrial and military base.

On August 9, as his boss reportedly questioned his sanity for believing that a single bomb could destroy a city the size of Hiroshima, a 25-kiloton plutonium bomb exploded above Nagasaki, throwing Mr Yamaguchi to the ground.

Guardian News & Media