The Chernobyl accident occurred on April 26, 1986 at the Chernobyl nuclear power plant in Pripyat, Ukraine (then part of the Soviet Union) and is regarded as the worst accident in the history of nuclear power. Large areas of Ukraine, Belarus and Russia were badly contaminated by the radioactive fallout, resulting in the evacuation and resettlement of roughly 200,000 people. About 60% of the radioactive fallout landed in Belarus. It is difficult to accurately tally the number of deaths caused by the events at Chernobyl, as most of the expected long-term fatalities, especially those from cancer, have not yet actually occurred and will be difficult to attribute specifically to the accident. A 2005 United Nations report attributed 56 direct deaths; 47 accident workers and 9 children with thyroid cancer and estimated that as many as 4,000 people may ultimately die from long term accident-related illnesses.