The Hiroshima bomb is the most devastating to have been used in real combat. But today’s nuclear weapons are far, far more powerful

Exactly 80 years since an atomic bomb was used in war for the first time, thousands bowed their heads in prayer in Hiroshima on Wednesday, as the city's mayor warned world leaders about the nuclear warheads that still exist today.

Thousands gathered in silence at the Hiroshima Peace Memorial Park on Wednesday, marking 80 years since the United States dropped the world’s first wartime atomic bomb on the city—an attack that killed tens of thousands and changed the course of history forever.