Wednesday marks the 69th anniversary of a Japanese tuna fishing boat's exposure to radiation from a US hydrogen bomb test on the Bikini Atoll, part of the Marshall Islands in the Pacific Ocean. People took to the streets in the city of Yaizu in Shizuoka Prefecture, central Japan, calling for the abolition of nuclear weapons.

The boat, Daigo Fukuryu Maru, was based in the port city. It was contaminated by radioactive fallout from the nuclear test on March 1, 1954, while it was operating in the South Pacific. The boat's 23 crewmembers were exposed to radiation.

More than 700 people from across Japan attended the rally in the city held for the first time in four years, after suspensions from the COVID-19 pandemic.

They marched for about 2 kilometers to the grave of Kuboyama Aikichi, who was among the crew. Kuboyama died six months after the incident. Participants prayed for peace in front of the grave.

The head of a foundation marking the incident, Yamamoto Yoshihiko, said Russian President Vladimir Putin uses nuclear threats and tries to justify the country's invasion of Ukraine. He said Putin should squarely face the desire held by Kuboyama that victims of atomic and hydrogen bombs never be produced again.

Supporters of the victims say that of the 23 former crewmembers, only two are alive. Ensuring that the incident is passed on to younger generations has increasingly become difficult.

Another former crewmember, Oishi Matashichi, died in March, 2021, at the age of 87.

His sister-in-law, Kawamura Keiko, said she has a sense of crisis that the number of those who know about the incident is decreasing. She added that she will continue talking about what Oishi experienced as his relative.