Hiroshima, Japan: Every weekend for more than 20 years, Shigeaki Mori sat in the hallway of his compact two-storey home making calls to people in the United States, asking, "Do you have a family member who died as a prisoner of war in Japan?"
He was searching for the families of 12 American POWs who died on Aug. 6, 1945, when the United States dropped an atomic bomb on the Japanese city of Hiroshima.
It was not until the 1970s that declassified US documents indicated the presence of the POWs in Hiroshima on that day. In the 1980s, Satoru Ubuki, a local university professor found their names and passed them on to Mori, a keen local historian.
An A-bomb survivor himself, Mori was determined to inform the families of what happened to their kin - many were not told the exact nature of the deaths - and he believed that the soul of the dead should be respected and remembered.
It was an arduous process - and one that is not over yet as Mori is now tracking down the details of British and Dutch POWs he believes also died in Hiroshima and Nagasaki, which was bombed three days later.
To find the American families he only had the surnames to go by so rang everyone he could find with that name, one by one.
"I had a map from Seattle to Texas ... It took me about three years (to find one family)," Mori, 77, said via a translator in the cluttered living room of his home in a Hiroshima suburb, sitting ramrod straight, hands on his lap.
With his limited English he prepared a questionnaire and, if he found the person had something to do with the POW, he asked the telephone operator to help, he recounted, laughing.
"It took me over 20 years ...I cannot remember how many I called," said Mori, a retired securities broker.
It was also costly. He would rack up monthly phone bills of 60,000 or 70,000 yen (around $250 to $300 in the 1980s).
Yet his tenacity paid off. He successfully contacted 11 families and registered the POWs with the city authority.
Their pictures in the Hiroshima Peace Memorial Hall among a sea of Japanese victims are a stark reminder of the bomb`s indiscriminate nature, a message Mori wanted to convey.
Mori, of slight build, serious and the epitome of Japanese stoicism, wears the achievement lightly on his sleeve.
"What I did was just what the families had to do but they had no clue how. They say they really appreciated me contacting them. I was really glad to hear their words," he said.
"I`m now researching about Dutch and British POWs, not just in Hiroshima but also Nagasaki." Mori says the whole process was cathartic for him too.
Eight-year-old Mori was on his way to summer classes when the world`s first nuclear attack occurred.
"As I was walking on (a) bridge, suddenly I felt a massive shockwave and a blast from above. I was blown off the bridge and fell into the river," he recalled.
Luckily the river was shallow and plants broke his fall but two other people on the bridge were burnt badly and one died.
After he regained consciousness, the morning was black.
"I couldn`t even see the 10 figures on my hands," he said, raising his palms for emphasis. He crawled out of the river and saw a woman walking towards him.
"She was swaying ... and holding something white. I realised she was holding the contents of her stomach."
The sounds of B-29 bombers filled the air and Mori, thinking another bomb was on the way, ran, stumbling over corpses.
He spent that night in an air raid shelter next to his former primary school, hungry, thirsty and terrified.
"That night was like hell ... Many people were in the schoolyard yelling in agony. There was nothing to eat or drink."
The death toll from the blast was estimated at about 140,000 by the end of the year, out of the total of 350,000 who lived in Hiroshima, 700 km (435 miles) southwest of Tokyo, at the time.
The bombing of Hiroshima and Nagasaki remain the only use of nuclear weapons in war.
The survivors, called hibakusha, continue to suffer the after effects of radiation.
Mori`s family struggled with bad health throughout their lives. Mori himself has problems with kidney, liver and heart that prevent him from long-haul air travel.
The hibakusha were criticised as being lazy - chronic fatigue is another consequence of radiation - and discrimination was rampant. Young women and men feared identifying themselves as they would have no suitors.
Mori`s wife, a classically trained pianist and singer, is also a hibakusha. They have two grown-up children.
The shadow of the bomb still looms large in modern-day Hiroshima, a thriving, bustling city crisscrossed by six rivers.
The peace park covers a large portion of the town centre and includes a cenotaph with the inscription: "Let all the souls here rest in peace, for we shall not repeat the evil".
Mori, who published a book in 2011 about the American POWs, is a pacifist like most hibakusha and worries the world is far from achieving peace.
"We should learn from the loss of lives in Hiroshima ... If war continues, people will suffer," he said.
The feelings of revenge against the United States have largely dissipated, Mori said, mainly because the US-occupied forces provided much-needed food when the survivors were hungry.
"I have complex feelings about it but it was so difficult for us to survive at the time. We appreciated American help."
In 2012, Mori met Clifton Truman Daniel, grandson of Harry Truman, the U.S. president who ordered the attack on Hiroshima.
"I felt like I was in a dream. I`m a victim of the atomic bombing and while he is not the person directly involved in it, he`s the grandson of the man who ordered (it)," he said.
"Now we shook hands, smiled and laughed. I cannot describe how moved I was. This is peace, I told myself."