A Japanese government official has confirmed that radiation has been detected in several locations in Fukushima Prefecture. The Nuclear and Industrial Safety Agency says in a report that nuclear fuel inside three reactors at the Fukushima Dai-ichi plant probably melted through not only the reactor cores, but also through the inner containment vessels. Andrew Dupuis has the details.

Japan's deputy chief cabinet secretary said that hot spots of radiation were detected in some residential areas in Minami Soma City as well as 10 other locations in the 60 kilometers radius from the crippled power plant.

He said, "Hot spots were found, meaning that there were certain spots with very high readings of radiation detected. We made this report and we have discussed on how to take this matter forward between the prefecture and the government."

Meanwhile, Mayor of Minami Soma City told the media in a press conference on Thursday that information needs to be transparent, in order to give a sense of security to the residents of the city.

He said, "After discussion with the government this morning, we know that it is not covering a large area, but rather pinpointed to a few households. Our discussion also was based on the possibilities of having to convince the resident living in such areas and evacuate."

Reports say that there are no immediate threat to human health from the radiation level in Minami Soma City, although the city is a short distance from the crippled nuclear power plant.

Earlier, trade ministry officials said all 54 of Japan's nuclear reactors may be shut by next April, if communities object to plant operating plans due to safety concerns. It will add more than 30 billion US dollar a year to the country's energy costs.

And all 19 reactors still running will need maintenance by April, 2012.