The hydrogen explosion at the No. 3 reactor of Fukushima Dai-ichi power plant, 150 miles north of Tokyo, injured 11 people, Reuters said. The blast was felt 25 miles away and reports said white smoke was seen billowing from the building.
Officials said the core of the reactor remained intact and radiation leakage was minimal, but Kyodo news agency said fears were growing of a third blast after falling water levels exposed cooling rods at the plant’s No 2 reactor.
Technicians were still battling to contain a potential meltdown at Dai-ichi’s No.1 reactor, which was hit by a similar explosion on Saturday. National strategy minister said No. 1 still posed the biggest risk, but there was “absolutely no possibility of a Chernobyl.”
The plant was plunged into crisis after backup safety measures that kicked in following Friday’s 8.9 magnitude earthquake were then affected by the powerful tsunami that washed ashore, engulfing vast tracts of northeastern Japan.
In their desperation to reduce the reactor's temperature, engineers have resorted to pumping in an untested mixture of seawater and boric acid. Authorities have declared an exclusion zone within a 15 mile radius of the plant and evacuated 210,000 people.
The death toll from the disaster continued to grow. About 2,000 bodies have been found washed up on the shores of Miyagi prefecture, which bore the brunt of the disaster, Kyodo said. About 1,000 were found on the Ojika Peninsula, and another 1,000 in the town of Minamisanriku, it said.
Authorities have said the death toll is expected to exceed 10,000, with at least 9,500 still unaccounted for in the coastal town of Minami Sanriku.
International efforts to help survivors were being hit radiation leaking from Fukushima. Low levels of radioactivity were found on 17 U.S. Navy helicopter crew members after they conducted relief missions from the USS Ronald Reagan, an aircraft carrier dispatched to provide help.
CNN said the U.S. Navy had repositioned ships and planes from its 7th Fleet — based in Japan — after detecting low-level contamination in the air and on its aircraft.
Japan’s Prime Minister Naoto Kan has said the earthquake, tsunami and nuclear threat have left his country facing its biggest crisis since the Second World War.
In a televised address to the public, Kan appealed to the country to come together in their time of crisis, and predicted the arrival of a Japanese-style New Deal sparked by huge demand as it recovers from the disaster.
“This is the worst crisis in Japan’s 65-year postwar history,” Kan said. “All of the people of Japan face a test as to whether they can overcome it. Together, I think we will.”
As grim details of the disaster continued to unfold, tales of miraculous survival brought brief moments of joy.
A Japanese rescue team Sunday managed to save the life of Hiromitsu Shinkawa, a 60-year-old man who survived the tsunami by clinging to the top of his roof. Shinkawa, found close to 10 miles out at sea, told his rescuers: "I thought today was the last day of my life."