Chernobyl disaster

On 26 April 1986, reactor 4 of the Chernobyl Nuclear Power Plant near Pripyat, Ukraine, exploded during a flawed safety test, causing the most destructive nuclear disaster in history, rated at the maximum severity on the International Nuclear Event Scale alongside Fukushima. A reactor core fire spread radioactive contaminants across the Soviet Union and Europe; the USSR established a 30 km exclusion zone, evacuated roughly 117,000 people, and did not publicly acknowledge the disaster until radiation was detected in Sweden two days later. Of 237 hospitalized workers, 134 showed acute radiation syndrome; long-term death estimates range from up to 4,000 to 16,000 across Europe.