The close marks the first steepest percentage fall in the Nikkei 's history . At more than 1,390 point , the Nikkei plunged one points , or nearly 17 percent . ( CNN ) -- Japanese stocks closed down 10.55 percent , recovering from deeper losses earlier in the session , as the nation grappled with a crisis at an earthquake-damaged nuclear power plant and the aftermath of last week 's earthquake and tsunami . Kan : Risk of further releases of radioactive material from Fukushima Daiichi plant `` very high '' Tokyo market opened shortly after `` explosive impact '' reported at nuclear reactor .
The close marks the first steepest percentage fall in the Nikkei 's history . At more than 1,390 point , the Nikkei plunged one points , or nearly 17 percent . Kan : Risk of further releases of radioactive material from Fukushima Daiichi plant `` very high '' Tokyo market opened shortly after `` explosive impact '' reported at nuclear reactor .