Ukraine has declassified almost 50 previously top secret documents related to the meltdown of the Chernobyl nuclear power plant, Russian news website Rosbalt.ru reported.
The documents shed light on immediate aftermath of the worst industrial nuclear accident in history, which took place at the plant 30 years ago on April 26, 1986.
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They reveal insufficient preparedness by the Soviet government in Ukraine and a lack of the equipment needed to quickly contain the disaster, Rosbalt.ru reported.
Dated between 1971 and 1981, the documents also include official memos and notes on the poor quality of the site's construction and violations of safety rules. There were 29 emergency shutdowns at the power station, eight of which were reportedly caused by the plant's personnel.
Experts have since determined that design flaws at the plant led to a power surge that ultimately triggered several explosions. The following meltdown of reactor number four caused the release of radioactive cloud into parts of Europe. Soviet authorities took several days to release information on the accident and to evacuate people from the surrounding areas.
The World Health Organization said in 2005 that up to 4 thousand people have died as a result of the disaster. Some 100,000 square kilometers of land was also contaminated with radiation, with the worst-hit regions in Ukraine, Belarus and Russia, Rosbalt.ru reported.