The close marks the third steepest price fall in the Nikkei 's history . At one point , the Nikkei plunged more than 10 points , or more than 14 % . Kan : Fear of further releases of radioactive material from reactors . ` ` very high '' The Tokyo market had opened shortly after the owner of the Fukushima Daiichi nuclear power plant in northeastern Japan reported an `` explosive impact '' at the plant 's No . 2 reactor , a day after a hydrogen explosion rocked another reactor . Tokyo Dome opened shortly after ` ` explosive impact '' reported at nuclear sites .
The close marks the third steepest price fall in the Nikkei 's history . At one point , the Nikkei plunged more than 10 points , or more than 14 % . Kan : Fear of further releases of radioactive material from reactors . ` ` very high '' Tokyo Dome opened shortly after ` ` explosive impact '' reported at nuclear sites .