Commemorations have been held in Hiroshima to mark 60 years since a US atomic bomb was dropped on the Japanese city. At 8.15 local time, a bell was rung to remember the exact moment 140,000 people were killed by the bomb and its aftermath. Japan’s Prime Minister Junichiro Koizumi led the ceremony in the city’s Peace Park, the epicentre of the blast.“Japan is the only country in human history to have suffered such a devastating attack and we will stick to our constitution and hold out for a non-proliferation treaty,” he said. Before releasing a thousand doves Koizumi added that after the bomb, the city had relentlessly pursued peace. Other speakers echoed his sentiments saying the tragedies in Hiroshima and Nagasaki should never be repeated. With Japan refusing to give up its Second World War campaign, US President Harry S.Truman warned it would face what he called a “rain of ruin from the air.” A plane called Enola Gay delivered the weapon that would change the course of history – in the first atomic bombing the world had ever seen. Nicknamed “Little Boy”, the attack generated a wave of heat which reached 4,000C and expanded across a radius of four and a half kilometres. Another ceremony will be held on Tuesday to commemorate the atomic bomb dropped on Nagasaki three days later.