"Certain countries are blatantly proclaiming self-centred nationalism and modernising their nuclear arsenals, rekindling tensions that had eased with the end of the Cold War", Matsui said, without identifying the nations.
Participants in Monday's ceremony - survivors, Prime Minister Shinzo Abe and representatives from 80 countries - observed a minute's silence at 8:15 a.m., the moment when the U.S. dropped its payload on the unsuspecting population 73 years ago.
Mayor Kazumi Matsui opened his address at the annual ceremony by describing the scene on August 6, 1945, and the agony of the victims, telling the audience to listen "as if you and your loved ones were there".
The group played a key role in campaigning for the Treaty on the Prohibition of Nuclear Weapons, which was approved by the United Nations in July past year. Now, the Associated Press reports a team of Japanese students have developed a virtual reality experience that recreates the attack, in an effort to highlight the lingering horrors the nuclear explosion wreaked upon the city - and prevent it from happening ever again. In order to gain cooperation from both sides, it is important for everyone to understand "the reality of the tragedy of nuclear attacks", he said, reiterating Japan's pledge to maintain its pacifist and non-nuclear principles.
Organizers of this year's observance hope to draw attention to the treaty and have the U.S.be the first of the nuclear powers to take the first steps in ratifying it.More news: Just how hot are the Red Sox?
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U.N. Secretary General Antonio Guterres said in his message the legacy of Hiroshima is one of "resilience" and sought continued moral support from hibakusha survivors.
Their average age is now just over 82.
Atomic bomb survivors and many visitors prayed for peace at the Peace Memorial Park near Ground Zero under the scorching summer heat. The bombings claimed 1 Lakh 40 thousand lives in Hiroshima and 74 thousand in Nagasaki.
Another Hiroshima resident Yoshinobu Ota, 71, was born after the bombing.
Although it's impossible to relive a moment in history, a group of the students have recreated the moment an atomic bomb dropped over the city through VR to portray the livelihood of people that was taken away as a result of the bombing. "We were only told what we needed to know, and keep your mouth shut". "I want Japan to work toward eliminating nuclear weapons", Ota added.