Japan on Wednesday marks 80 years since the US dropped an atomic bomb on the city of Hiroshima during the last days of World War II, killing close to 80,000 people in the initial blast.

The memorial ceremonies taking place in Hiroshima on August 6 and Nagasaki three days later will attract thousands of people from across the world. There will, however, be fewer survivors - known as the "hibakusha" - than last year.