A letter written by Albert Einstein in 1939 to then-United States President Franklin D Roosevelt warning that Nazi Germany might harness nuclear research to invent an atomic bomb, which encouraged the US to develop the world’s first nuclear bombs, is going up for auction.

Einstein’s letter warning FDR about threat of Nazi nuclear bomb may sell for $4 million

It's been 75 years since America dropped the world's first atomic bomb on Hiroshima. For survivors, the war isn't over yet. Discarded N-treaties, faster missiles, cyber-attacks, and artificial intelligence - the new nuclear threats are greater than before. WION's Palki Sharma tells you why the world isn't any wiser.

Gravitas: 75 Years After Hiroshima | Will new tech raise the threat of nuke war?

Prime Minister Shinzo Abe, in his speech at the ceremony, said Japan is committed to nuclear weapons ban but said a nuclear-free world could not be achieved overnight and that it has to start from dialogue between opposite sides.

Japan: 75 years since first atomic bombing | Hiroshima Bombing Anniversary | Shinzo Abe

Japan marks 75th anniversary of Hiroshima atomic bombing | World War 2 | WION | World News