Japanese authorities have widened the evacuation area to 20kms around the stricken Fukushima nuclear power plant.
Authorities have told people within that radius to stay indoors.
45,000 people who live within a six-mile radius of the reactor have been evacuated and several workers have been injured, one seriously.
The walls and the roof of the nuclear power plant have been destroyed in the explosion and the Tokyo authorities are going to send a 'hyper rescue team' to the plant.
Radiation levels are now higher per hour, more than is permitted in a year at the Fukushima Number One plant.
The Japanese media has reported that nuclear authorities expect that serious damage to the reactor container is "unlikely".
Elsewhere, it has been reported that the Japanese military has found 300 to 400 bodies in Iwate's Rikuzentakata City.
At least 700 people have died so far and thousands are missing.
Nearly a quarter of a million people are in emergency shelters.