Tokyo Electric Power Company said on 15th that white steam is emitting from Fukushima No.1 Nuclear Plant's Unit 3, and an explosion hit the Unit 4, which caused fire. It is reported that the explosion of the Unit 4, similar to the previous ones, is a hydrogen explosion. According to Tokyo Electric Power Company, Fukushima No. 2 Nuclear Power Station Unit 4 is in a stable "low" state, out of a state of emergency. So far, other three units declared a state of emergency have been out of state of emergency.
Naoto Kan, Japanese Prime Minister, instructed that the evacuation of residents around the first nuclear power plant in Fukushima expand from 20 km to 30 km.