On May 25, 1986, the Chernobyl nuclear power plant in Ukraine suffered a catastrophic explosion during a late-night safety test. The explosion released radioactive particles into the atmosphere, contaminating much of Europe. Over 30 workers were killed in the immediate aftermath, and long-term effects of radiation exposure led to thousands of cancer-related deaths. The Soviet government initially tried to cover up the extent of the disaster, but it eventually became one of the most widely known nuclear accidents in history. The event prompted global changes in nuclear policy and safety protocols.