A SIREN wailed and a bronze bell rang as Nagasaki marked the moment 60 years ago when an American plane dropped a plutonium bomb, killing 80,000 people and sealing Japan’s Second World War defeat.

A siren wailed and a bronze bell rang as Nagasaki marked the moment 60 years ago when an American plane appeared in its skies and dropped the “Fat Man” plutonium bomb, killing 80,000 people and sealing Japan’s Second World War defeat.