Fukushima: Burning spent fuel rods spiked radiation levels

Tokyo: Even as reports began circulating around the globe about a spike in radiation levels at the Fukushima Daiichi nuclear park, leading to fears that a meltdown in the reactors may have begun, the plant's owners have offered another explanation.  Spent fuel rods, which are radioactive and still lying in a pool adjoining a nuclear reactor at the park, may have burned in a blaze noticed on Tuesday and were responsible for the radiation spike, the Tokyo Electric Power Co said.

The blaze started Tuesday morning but was later extinguished, Tokyo Electric Power Co (TEPCO) said. It was unclear how much radioactive material may have been emitted, or what kind of health threat that could pose.

Chief government spokesman and cabinet secretary, Yukio Edano, said Tuesday afternoon that radiation readings at the plant's front gate had returned to a level that would not cause "harm to human health."

More than 200 tons of spent nuclear fuel is stored in pools adjacent to the reactors. Those cooling pools depend on continually circulating water to keep the fuel rods from catching fire. Without power to circulate the water, the rods would heat up and the water boil away leaving the fuel rods exposed to air.

Earlier, an aerial photograph of the Fukushima complex appeared to show that the spent fuel pool was steaming hot, indicating that the water was boiling off, outside experts had said.

Japanese officials had earlier informed the International Atomic Energy Agency that radioactivity was "being released directly into the atmosphere" during the fire, according to an IAEA statement.