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.

Hiroshima is marking the 80th anniversary of the U.S. atomic bombing of the western Japanese city on Wednesday.

As the world marks the 80th anniversary of the first use of a nuclear weapon on the Japanese city of Hiroshima near the end of World War II, the planet is closer to seeing them used again than it has been in decades,