Tokyo Electric Power Co., the plant's operator, said 120 tons of water leaked early Saturday as workers transferred it from a leaking tank to another one, The Asahi Shimbun reported. Company officials said none of the tainted water has gotten into the ocean.
Because it passed through a filtering system before leaking, the water had about half the radioactivity of untreated water, TEPCO said.
Fukushima was heavily damaged in March 2011 by the earthquake and tsunami that hit Japan.
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