There was no explosion in the reactor container at a nuclear power station in the earthquake-hit Fukushima prefecture, Japanese Chief Cabinet Secretary Yukio Edano said on Saturday.
He said the wall of the reactor turbine building collapsed at the Fukushima Number One power plant earlier in the day but that the reactor container itself suffered no damage, NHK Television reported.
The reactor is covered with a steel container and is placed in the reactor turbine building which is made of steel-reinforced concrete, Edano said, adding that the explosion was triggered when a combination of hydrogen and oxygen ignited.
Although radiation around the plant earlier was on the rise, it was gradually decreasing, he said.
He provided no figures, but the Fukushima prefecture said earlier in the day the radiation level near the Number One nuclear power station rose to 1,015 mircrosieverts per hour.
A Japanese nuclear safety panel said radiation levels were 1,000 times higher than normal in a control room and eight times higher than normal just outside the plant.
Iodine
Japanese authorities are preparing to hand out iodine, which helps protect the body from radioactive exposure, to residents in the area near the nuclear power plants hit by a massive earthquake.
The U.S. and France also said they had plans to distribute doses of stable potassium iodine.
Media reports said earlier on Saturday the cooling system had failed at the Fukushima nuclear plant in northeastern Japan. Pressure was eased and steam was released from the nuclear reactor to prevent any meltdown.
Evacuation
The Fukushima prefectural government has expanded the evacuation area around Fukushima Number 1 Power Station from an earlier established 10-kilometer radius to a 20-kilometer radius.
The prefectural government is working to determine which towns and villages fall under the new evacuation order, NHK Television said.
'No Chernobyl'
Naoto Sekimura, a professor at the University of Tokyo, told the Associated Press a major radioactive disaster was unlikely.
"No Chernobyl is possible at a light water reactor. Loss of coolant means a temperature rise, but it also will stop the reaction," he said. "Even in the worst-case scenario, that would mean some radioactive leakage and equipment damage, but not an explosion."
The Fukushima prefecture authorities urged the people in the area to close windows, turn off air conditioners and stay at home.
Aid
Some 70 search-and-rescue teams from 45 countries have offered aid to Japan in the aftermath of a massive earthquake and tsunami.
Japan asked Russia on Saturday to increase energy supplies and Moscow is ready to deliver up to 150,000 tons of liquefied natural gas and increase gas supplies, Deputy Prime Minister Igor Sechin said.
Sechin said Russia's Suek and Mechel companies would meet next week to consider the possibility of boosting coal supplies by 3-4 million tons.
Additional electricity could also be supplied via the existing underwater cable, he said.
Russia is ready to provide any - energy, rescue and psychological - support, Sechin added.
Russian Prime Minister Vladimir Putin said earlier in the day liquefied natural gas supplies to Japan should be stepped up if requested.
Northern Japan was hit by a massive 8.9-magnitude earthquake and a ten-meter tsunami wave on Friday. Authorities said the death toll could exceed 1,000 with 784 people still missing. Over 1,130 people were injured.
Rescuers have recovered 400-500 bodies in the Miyagi prefecture.
The official death toll currently stands at around 600.
TOKYO, March 12 (RIA Novosti)
