A third explosion in four days rocked the earthquake-damaged Fukushima Dai-ichi nuclear plant in northeast Japan early Tuesday...a little after four this afternoon Peoria time.
The explosion adds to fears the plant is heading towards a total meltdown.. and is raising concerns in the U-S as well.
The blast at Dai-ichi Unit 2 followed two previous hydrogen explosions at the plant as authorities struggled to prevent the catastrophic release of radiation in the area.
The plant's owner said the explosion occurred near the suppression pool in the reactor's containment vessel.
The pool was later found to have a defect.
Radiation levels in the air surrounding the plant have risen four-fold after a fresh explosion at the site today.
NBC News reports that It now seems that the nuclear fuel rods inside all three functioning reactors at the complex are melting.
Some experts would consider melting fuel rods a partial meltdown of the nuclear reactor.
Others, though, reserve that term for times when nuclear fuel melts through a reactor's innermost chamber but not through the outer containment shell. But, that could be happening too.
If a complete reactor meltdown were to occur, a wave of radiation would be released, resulting in major, widespread health problems.