The comment by Tokyo Electric Power Co follows a U.S. academic journal Science article that said high radiation levels in bottom-dwelling fish caught off Fukushima prefecture indicate continued radiation leaking from the Fukushima Daiichi nuclear power plant.

Asked if Tokyo Electric, also known as Tepco, could confirm that the plant is not leaking radiation into the sea any more, a spokeswoman said: “Tepco cannot say such a thing, but we have confirmed that radiation levels are declining in both the sea water and seabed soil around the plant.”