For survivors of the world's first nuclear attack, the day America unleashed a terrible bomb over the city of Hiroshima remains seared forever in their minds.
Though their numbers are dwindling and the advancing years are taking a toll, their haunting memories are undimmed by the passage of more than seven decades.
On the occasion of Barack Obama's offering of a floral tribute on Friday at the cenotaph in Hiroshima Peace Memorial Park -- the first ever visit by a sitting US president -- some of them share their stories with AFP.
Emiko Okada, now 79, was about 2.8 kilometres (1.7 miles) from ground zero and suffered severe injuries in the blast. Her sister was killed.
"All of a sudden a flash of light brightened the sky and I was slammed to the ground. I didn't know what on earth had happened. There were fires everywhere. We rushed away as the blaze roared toward us.
"The people I saw looked nothing like human beings. Their skin and flesh hung loose. Some children's eyeballs were popping out of their sockets.
"I still hate to see the glow of the setting sun. It reminds me of that day and brings pain to my heart.
"In the aftermath, many children who had evacuated during the war came back here, orphaned by the bomb. Many gangsters came to Hiroshima from around the country and gave them food and guns.
"President Obama is a person who can influence the world. I hope that this year will be the beginning of knowing what actually happened in Hiroshima and Nagasaki under the mushroom clouds."
Keiko Ogura, now 78, has devoted her life to keeping alive the memory of the devastating day.
"Shortly after (the bomb exploded) it rained. It was a sticky black rain and made my clothes wet.
"I saw a line of seriously burnt people, like silent ghosts.
"Suddenly, a girl grabbed my leg and said in a weak voice: 'Give me water.' Others also said: 'Water. Water.'
"I brought water to them, but some died right after they drank it. I regretted giving it to them.
"I saw smoke from a nearby park where bodies were being cremated. Sometimes I could smell the bodies burning.
"We faced the horror (of nuclear weapons). I tell everybody that it was hell. But they don't understand.
"There is no peace in Hiroshima. There is horror here."
Park Nam-Joo, now 83, is an ethnic Korean, who has suffered from breast and skin cancer because of the radiation she was exposed to that day.
An estimated 20,000 Koreans were among the dead in Hiroshima. Many had been taken to Japan as forced labourers during its 1910-1945 colonial rule of the Korean peninsula:
"Everything was broken to pieces. Everywhere was rubble. It's beyond description. It was inhumane.
"Hiroshima was a sea of fire. People bled from everywhere on their bodies: 'I'm burning. I'm burning. Please help,' they cried.
"The wounds of the living were infested with maggots. There was no medicine for it.
"People say human life is to be revered but the lives of those who died in the atomic bombing were just like those of insects.
"I still shed tears when I recall the scene. Many people don't want to remember that.
"I want people to know that not only Japanese but Korean, Chinese and others also suffered in the atomic bombing.
"I'm Catholic. Wearing a rosary and with a statue of the Virgin Mary next to me, I pray at night for a peaceful passage to heaven."