Events similar to or like Chernobyl disaster

2011 nuclear accident at the Fukushima Daiichi Nuclear Power Plant in Ōkuma, Fukushima Prefecture, Japan. Caused by the 2011 Tōhoku earthquake and tsunami. Wikipedia

Radioactive contamination accident that occurred on 29 September 1957 at Mayak, a plutonium production site for nuclear weapons and nuclear fuel reprocessing plant located in the closed city of Chelyabinsk-40 in Chelyabinsk Oblast, Russian SFSR, Soviet Union. The second worst nuclear incident after the Chernobyl disaster. Wikipedia

Explosion occurred in a Dōnen plant, and on 30 September 1999, a serious criticality accident happened in a JCO plant. Wikipedia

Fire that caused an interruption of the cooling system in the Vandellòs Nuclear Power Plant, Catalonia on 19 October 1989. At the end of Francoist Spain, France sold Spain a UNGG reactor. Wikipedia

The 1961 Kurenivka mudslide occurred on March 13 in Kyiv, Ukrainian SSR, Soviet Union. The mudslide started at the edge of the Babi Yar mass murder site and dumped mud, water, and human remains into the streets of Kyiv. Wikipedia

The process of internal disintegration within the USSR, which began with growing unrest in its various constituent republics developing into an incessant political and legislative conflict between the republics and the central government, and ended when the leaders of three primal republics (the Russian SFSR, the Ukrainian SSR and the Byelorussian SSR) declared it no longer existed, later accompanied by 11 more republics, resulting in President Mikhail Gorbachev having to resign and what was left of the Soviet parliament formally acknowledging what had already taken place. The failure of the 1991 August Coup, when Soviet government and military elites tried to overthrow Gorbachev and stop the "parade of sovereignties", led to the government in Moscow losing most of its influence, and many republics proclaiming independence in the following days and months. Wikipedia