In the final stages on World War II, on 6th August 1945, the United States used an atomic bomb to attack the Japanese city of Hiroshima.
It was followed by a further atomic bombing of Nagasaki on the 9th August. The two bombings are the only use of nuclear weapons in war to date and lead japan to surrender to the Allies.
The attacks followed months of air raids and warnings from the Allies - on 26 July 1945, they threatened Japan with "prompt and utter destruction" unless they surrendered.
The codenames for the two were 'Little Boy' (Hiroshima) and 'Fat Man' (Nagasaki).
Within the first two to four months of the Hiroshima bombing, 90,000 to 120,000 people were killed. Nagaski suffered 60,000 to 80,000 casualties.
The ethical justification of the bombings, especially the use of nuclear weapons, is still debated and criticised today.
