Battle to keep control of nuclear plant in Japan
Japan says it is stepping up efforts to cool overheating fuel at the tsunami-hit Fukushima Daiichi nuclear plant.
The British government's chief scientific adviser says he is 'extremely worried' about the worsening situation at the Fukushima nuclear site.
Japanese authorities have been using increasingly desperate methods to cool down reactors at the complex, and there is concern over a lack of clear information.
David Shukman reports.
17 Mar 2011