In 1945 the world’s first nuclear explosion was made from an US aircraft in the city of technology on 6th august . PM Shinzo Abe attended a ceremony, held at Hiroshima's memorial park before thousands of lanterns were released on the city's Motoyasu river.
The bombing in Hiroshima, and a second one on Nagasaki three days later were credited with bringing an end to the World War Two. But it took away the lives of at least 140,000 people in the city.
A US B-29 bomber called the Enola Gay dropped the uranium bomb, exploding some 600m (1,800ft) above the city, around 08:10AM on 6th August 1945.
On that day , minimum 70,000 people were believed to have been killed. Many more died of horrifying injuries caused by radiation poisoning in the days, weeks and months that followed.
People across Japan have observed a minute's silence to mark the anniversary of that deadliest attack. In Hiroshima a bell tolled at 08:15 local time while the US aircraft dropped the bomb that flattened the city centre.
Addressing 40,000 people who attended the commemoration ceremony at Hiroshima's peace park near the epicentre of the 1945 attack, Mr Abe called for worldwide nuclear disarmament.
He said that that atomic bomb not only killed thousands of people in Hiroshima but also caused unbearable suffering to survivors.
The Prime minister said in the ceremony. "Today Hiroshima has been revived, and has become a city of culture and prosperity. Seventy years on I want to reemphasise the necessity of world peace."
By Prakriti Neogi