A version of this article was originally published on Saturday.

TODAY marks 70 years since the atomic bombing of Hiroshima and Nagasaki.

The first blast happened in Hiroshima on 6 August, 1945.

It is estimated that between 60,000 and 80,000 people were killed instantly when the bomb fell for 44.4 seconds before detonating 580 metres above the ground.

Subsequently, a large number of people died from the effects of radiation sickness, putting the final death toll at around 135,000 – although many estimate it to be higher.

It was followed by the attack on Nagasaki on 9 August, 1945. The estimated total death toll for the second attack is around 75,000.

A picture of the Hiroshima blast taken from around 10 km away 30 minutes after detonation Source: Honkawa Elementary School via Wikicommons

The attacks effectively brought about the end of World War Two.

By the time the United States had successfully trialled nuclear weapons Germany had already surrendered in Europe.

Japan were seen as a stubborn opposition, continuing their resistance to the United States despite clear indicators that they were likely to lose the war.

The explosion over Hiroshima Source: 509th Operations Group via Wikicommons

In new scientific research funded by the Radiation Effects Research Foundation in Japan, 94,000 atomic bomb survivors have been examined. The study looks at a time period starting five years after the incident in 1950 and continuing through to the present day.

In the subjects examined it was found that there was a stark increase in the instances of cancer. A higher risk was found in those exposed as children or as younger adults.

Another finding from the research was those affected by the blasts do not appear to have passed on any of the side effects to their children.

The atomic cloud over Nagasaki from Koyagi-jima Source: Hiromichi Matsuda via Wikicommons

The bombings remain a difficult issue when it comes to US – Japanese relations. The United States has never apologised for the attacks.

Nagasaki picture at around the turn of the century Source: Unknown via Wikicommons

In modern times, Hiroshima and Nagasaki have returned to become fully functioning societies.

Following the attacks the national government provided specialised funding to assist in the rebuilding Hiroshima, with the establishment of the Peace Memorial City Hiroshima fund.

In Nagasaki the rebuilding effort was notably slower. Today it is a prominent port city and has a population of around 1.4 million.

Nagasaki after the bomb attack in 1945 Source: Associated Press/File

Hiroshima before the bomb attack of 1945 Source: Hiroshima Peace Memorial Museum

The ruins of Hiroshima after the bomb attack Source: Imperial War Museum via Wikicommons

Those that survived the attack were made to endure horrendous injuries for the rest of their lives.

Speaking to Reuters earlier this year, one of the survivors, Shuntaro Hida, described the “cruellest aspect” of the attacks as being the “life-destroying after-effects”.

A victim of the Hiroshima bombing Source: アサヒグラフ via Wikicommons

Sunji Yamagushi, who survived the atomic bomb over Nagasaki, shows his scars at a press conference in Los Angeles in 1980 Source: AP Photo/File

An example of nuclear burn patterns through cloth Source: Eisei Ishikawa via Wikicommons

Ahead of the commemorations this coming week, the Mayor of Hiroshima, Kasumi Matsui, has called for leaders around the world to work together to prevent anything similar ever happening again.

Quoted in the Japan Times, on the issue of whether US officials should apologises, Matsui has said, “I don’t think we should make an issue of whether they should apologise or not… What I want leaders to do when they visit Hiroshima is to vow toward the future that they will never allow this kind of thing to happen again.”

Doves being released at Hiroshima Peace Memorial Park to mark the 65th anniversary of the event Source: Kyodo/AP/Press Association Images