Another explosion occurred on Monday at the quake-hit Fukushima No. 1 nuclear power plant, 230 km north of Tokyo, injuring at least 11 people, but the reactor’s container was not damaged.
TV footage showed that the top of the building housing the reactor was blown off.
“The chamber housing the reactor’s radioactive core is intact after the 11: 01 a.m. (0201 GMT) blast at the troubled No. 3 reactor of the plant, but the possibility of a large radiation leak is very small,” Chief Cabinet Secretary Yukio Edano told a press conference.
“Today’s hydrogen explosion blew away the roof and the walls of the building housing the container of the No.3 reactor was similar to an explosion Saturday at the No. 1 reactor of the same plant, ” Edano said.
“The power station’s operator Tokyo Electric Power Co. continues pumping seawater to cool down the No. 3 reactor,” the top government spokesman said, adding that it has so far observed no abnormal rise in radiation around the compound of the plant.
The Fukushima No.1 nuclear plant was damaged following Friday’s magnitude 9.0 quake.
Tokyo Electric Power Co. separately said 11 people, including seven workers at the plant, were injured.
Following the blast, the Nuclear and Industrial Safety Agency urged residents within a 20-kilometer radius to take shelter inside buildings immediately. About 600 people are thought to be still in the area when the explosion took place.
Fears of an explosion rose earlier in the day when the water level of the No. 3 reactor dropped and exposed fuel rods, and a reaction with the steam generated a large amount of hydrogen.
On Saturday, Tokyo Electric Power Co. notified the government that the No.3 reactor lost its cooling functions and began injecting water into it as an effort to reduce pressure and temperature to save the reactor from a possible meltdown.