Fukushima alert level rise 'significant'
21 August 2013 Last updated at 10:12 BST
The increase of the severity level of a radioactive water leak at the Fukushima plant is being regarded as a "significant" rise in Japan.
The leak was first classified as level one, but has now been upgraded to level three of a possible seven on the International Nuclear and Radiological Event Scale.
Rupert Wingfield-Hayes reports that the move is seen as a confirmation of poor management of the disaster since the plant was damaged in the 2011 earthquake and tsunami.