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The Chernobyl disaster was nuclear accident which took place at the Chernobyl Nuclear Power Plant in the north of the Soviet Union on 25 April 1986. The accident occurred during a test on one of the nuclear reactors which ended provoking an explosion due to a flawed plant design as well as inadequately trained workers who made numerous errors and ignored safety warnings. During the explosion, a great quantity of noxious substances was released into the atmosphere. The result was the death of 31 people at the nuclear plant, the evacuation of more than 100,000 people from the nearby cities, and other long term effects like bad health conditions to the many people who were in the area which caused many more deaths, and a loss of a city as that area is still contaminated today. The accident also affected other countries in Europe and even North America as lots of people still received huge quantities of radiation there.
To help the region recover from the disaster, the IAEA provided support to Ukraine, Belarus and Russia in environmental remediation, decommissioning and management of radioactive waste and strengthening the safety levels at the Chernobyl nuclear power plant — in several instances in cooperation with other United Nations organizations. The IAEA also helped with evaluation and assessment of the accident site and its consequences.