NAGASAKI, Japan — The son of the U.S. Marine photographer who filmed a boy carrying his dead brother in the aftermath of the atomic bombing of Nagasaki has shaken hands with Pope Francis.

Francis visited the Nagasaki ground zero Sunday and demanded world leaders renounce atomic weapons and the Cold War-era doctrine of deterrence.

Tyge O’Donnell, the son of Joseph O’Donnell, was invited to the event as a guest. His father’s iconic photo was printed on cards that Francis delivered in 2017 in his anti-nuclear message.

O’Donnell, his camera hanging from the neck, approached Francis as the pope was greeting people after the speech. O’Donnell described the encounter as a “phenomenal experience.”

He says the pope’s eyes were “very very kind and he was well spoken. I was just amazed. I am very pleased to have met him.”

There is controversy surrounding Joseph O’Donnell, who reportedly often took credit for photographs that were not his, and in 2007 the New York Times reported there are several “discrepancies” about his work.

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In story the newspaper published just over a month after his death, “scrutiny has extended to pictures he took as a 23-year-old marine in Japan that he said had been hidden in a trunk in his home until he unearthed the negatives in 1985.”

O’Donnell had claimed he had put the negatives away after the war because the images of the nuclear destruction of Hiroshima and Nagasaki were too troubling to be published at the time.

Those photos included the one circulated by Pope Francis in 2017.

They were first exhibited in the 1990s, and then published in a book in 2005, Japan 1945: A U.S. Marine’s Photographs From Ground Zero.

Some experts have questioned how he was able to get photos from both cities, which are nearly 200 miles apart.

The New York Times said, “The authenticity of those pictures has not been disproved.”

O’Donnell’s family has defended the photographer, saying the discrepancies were because he suffered from dementia in his later years.

Crux staff contributed to this report.

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