The container of the No. 3 reactor of Japan's quake-hit Fukushima No.1 nuclear power plant is feared to have been damaged and may have leaked radioactive steam Wednesday, emitting high-level radiation, Kyodo News Agency quoted government spokesman Chief Cabinet Secretary Yukio Edano as saying.

According to Tokyo Electric Power Co. (TEPCO), the operator, the radiation level briefly topped 2 milisievert at the plant.

Smoke was seen rising from the No. 3 reactor since around 8:30 a.m. local time. TEPCO said earlier that it can not check smoke at Fukushima plant as radiation is too high.