Tokyo, Aug 6 : Japan on Saturday marked the 77th anniversary of the atomic bombing of Hiroshima that took place in the final days of the Second World War. A moment of silence was observed at 8.15 a.m., the exact moment when a uranium bomb dropped from a US bomber detonated over the city on August 6, 1945, killing around 140,000 people by the end of the year and exposed many more to harmful radiation, reports Xinhua news agency. At a memorial ceremony held at the Peace Memorial Park, Hiroshima Mayor Kazumi Matsui cautioned in the Peace Declaration that dependence on nuclear deterrence is gaining momentum in the world. "We must immediately render all nuclear buttons meaningless," he said. Also in attendance at the ceremony were Prime Minister Fumio Kishida, representatives from 99 countries, as well as UN Secretary-General Antonio Guterres, the first chief of the world body to attend the event in 12 years. In his speech, Guterres warned that a new arms race is accelerating. The Prime Minister said "Japan will pursue this goal despite global security tensions, and while following the three principles of not possessing, producing or permitting the introduction of nuclear weapons into the country". More than 3,000 members of the public also turned out for the ceremony, a substantial increase on the crowds in 2020 and 2021, the first two years of the coronavirus pandemic, says public broadcaster NHK. Officials placed a list of victims of the bombing back in a cenotaph, following the addition of the names of 4,978 people who died or were confirmed dead over the past year. The total now stands at 333,907. The average age of atomic bomb survivors is now more than 84. /IANS