The threat of nuclear catastrophe intensified in Japan, after two more explosions at the devastated Fukushimi Dai-ichi Nuclear Power Plant had government officials imploring people within 18 miles of the facility to remain indoors for fear of being exposed to nuclear radiation. Late in the day, officials abandoned the nuclear facility altogether, deeming it too risky to stay. Elsewhere, a towering amount of work still needed to be done to count the cost — in lost money and lives.

The lack of water to cool the nuclear reactors had officials intensely worried — especially in the wake of recent aftershocks and fires — and the backup plan shaping up on Wednesday was to use helicopters to pour water on the reactors from above. Already, a no-fly zone was being enforced around the reactors, to ensure that a cloud of radiation didn't affect any aircraft. At last report, the cloud was heading out to sea. The Dai-ichi plant was one of several that had been affected by the 9.0 earthquake and subsequent tsunami.

Officials of Prime Minister Naoto Kan's government reported that radiation in Tokyo, the capital, had reached 10 times the normal rate but had since dissipated. Tokyo is a bit far away from the nearest troubled nuclear reactor, but Tokyo residents still went into stock-up mode after enduring a 6.4-magnitude aftershock, emptying many stores of such supplies as flashlights, candles, and portable radios.

Embassies of other countries advised their staff to leave affected areas, as did leaders of multinational companies. The country's Nikkei index of stocks showed a second straight day of big drops, ending in a two-day total of $620 billion value lost. Tourists have left the country in droves, if they could get out. Japan canceled large numbers of airline flights in the first hours and days after the tsunami first began washing away whole buildings and villages.

Tens of thousands of people remained missing, and many were presumed dead. Millions of people were confronting near-freezing temperatures without the benefit of electricity or running water.

The last disaster of large magnitude to hit Japan was the Kobe earthquake, in 1995. The official death toll from that quake was about 6,000. Japanese officials fear that the death toll from this most recent quake-tsunami combination could be far greater.