I think this counts as an Oh-my-God-moment:
An explosion rocked one of Japan's nuclear power plants Saturday, causing a portion of a building to crumble, sending white smoke billowing into the air and prompting Japanese officials to warn people in the vicinity to cover their mouths and stay indoors.
In what may become the most serious nuclear power crisis since the Chernobyl disaster, the explosion followed large tremors at the Fukushima Daiichi No. 1 reactor Saturday afternoon, injuring four workers who were struggling to get the quake-stricken unit under control.
Earlier, Japan's Nuclear and Industrial Safety Agency had warned that the reactor, whose cooling system had been crippled by the giant earthquake on Friday, could be nearing a meltdown and that two radioactive substances, cesium and radioactive iodine, had already been detected nearby.