"Where does that 400,000 figure come from? Sounds like a heck of a lot of bodies to hide."It did not happen overnight. Large areas of Belarus and Ukraine and some parts Russia were affected. In the decades that followed, and in the post-soviet breakup it was pretty hard to keep tabs. The Soviet govt was always secretive about everything and often they told doctors to not report nuclear related causes of death, this practice dates back to their 50's nuclear tests. http://www.amazon.com/Legacy-Chernobyl-Zhores-Medvedev/dp/0393308146/ref=sr_1_fkmr1_2?ie=UTF8&qid=1300486488&sr=1-2-fkmr1
Not only didn't happen overnight it didn't happen at all. There has been numerous studies by all kind of health organizations. It was a very bad event and many areas are still contaminated and will be for a long time so you don't need to make up numbers.