The problems with the Fukushima nuclear plant have raised questions over Tepco’s future Tokyo Electric Power (Tepco) has said there have been new partial meltdowns in fuel rods at its damaged Fukushima nuclear power plant.
The company said that the fuel rods are in its Number 2 and Number 3 reactors.
Tepco has been trying to contain radiation that started leaking from the plant when it was hit by the 11 March earthquake and tsunami.
The company said that it planned to stick to its timetable of getting the plant under control by January.
“Based on our analysis, we have reached the conclusion that a certain amount of nuclear fuel has melted down,” Ken Matsuda, a Tepco spokesman told the BBC.
Tepco had said earlier this month that rods at its Number 1 reactor had also melted down.
The company has been trying to cool the reactors and get the unstable fuel rods back under control.
Last week, the president of Tepco, Masataka Shimizu, resigned. He will be replaced by managing director Toshio Nishizawa.
The announcement came on the same day the company reported an annual loss of 1.25tn yen ($15.3bn; £9.4bn).
Tepco’s loss is a record for a non-financial firm in Japan.
The company’s share price has fallen more than 80% since the earthquake.
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