Workers at the crippled Fukushima nuclear plant in Japan say they have seen steam rising from one of the damaged reactor buildings, for the second time in less than a week.
The company that runs the plant – Tokyo Electric Power Company, also known as Tepco, says it has not been able to establish where the steam is coming from.
The news comes a day after Tepco admitted for the first time that radioactive contaminated water is still leaking from the plant in to the sea.
Rupert Wingfield Hayes reports from Tokyo.
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