gerhard schindler was reportedly told to go by the chancellor's office today.official reason has been given for the shakeup. it was the worst nuclear accident that the world has ever seen. 30 years ago today, an explosion at chernobyl sent a radioactive cloud across europe. ceremonies have been taking place in ukraine to mourn the victims. some 50 decibels directly attributed to the accident, but according to some estimates that number could end up in the thousands. >> they gave their lives to save others. in kyiv today, people pay their respects to those soldiers and civilians who died of duty. a few men who took part in the cleanup of the reactor defied the odds and survived their experiences. oleg was one of them. >> i have lived 30 years even though the doctor said i only had five. i have been lucky, but we have been living in an affected company -- country for 30 years now. we will not have to suffer another decade from the radiation, but our children will. >> the ukrainian president led the memorial services in kiev. he laid flowers there and gave rewards