Chernobyl disaster

The reactor accident at the Chernobyl nuclear power plant was the worst in history, resulting in a severe nuclear meltdown. On 26 April 1986 at 01:23:40 a.m. reactor number four at the Chernobyl Nuclear Power Plant located in the former Soviet Union near Pripyat in Ukraine exploded. Further explosions and the resulting fire sent a plume of highly radioactive fallout into the atmosphere and over an extensive geographical area.
See more at Wikipedia.org...