The Chernobyl disaster was a catastrophic nuclear accident that occurred on April 26, 1986, at the Chernobyl Nuclear Power Plant in the (then Soviet) Ukraine. During a late-night safety test, Reactor No. 4 exploded due to design flaws and human error. This released large amounts of radioactive material into the atmosphere, spreading across Europe. Two workers died immediately, and many others later suffered from radiation sickness. Thousands of people were evacuated, especially from the nearby c