Meltdown occurred at Reactors No. 1, No. 2, No. 3 and No. 4 of the Fukushima Nuclear Power Plant causing radioactive substance leakage. This is leading to the destruction of the containment vessel.

All the outer walls of Reactors No. 1, No. 2 and No. 3 burst and the containment vessels of Reactors No. 2 and 3 were damaged.

A spokesman for the Tokyo Electric Power Co. expressed concern that spent fuel rods of Reactor No. 4 might spark off nuclear fission chain reaction.

Meanwhile, the water temperature keeps rising at Reactors No. 5 and No. 6 due to the trouble in the cooling system. They had been under maintenance when the quake struck the area.

The director general of the International Atomic Energy Agency said at a press conference that the situation at the Fukushima Nuclear Power Plant ''continues to be serious'' due to large radioactive substance leakage.

The U.S. took a measure to test foods from Japan for radioactivity in the wake of Thailand, Singapore and other Asian countries.

Meanwhile, the Japan Police Agency made public that the quake death toll swelled to 6,405 and 10 259 reported missing as of 11:30 of Friday.