5:56 - "Fire breaks out at Japan Fukushima Daiichi No. 4 reactor," reports Reuters flash.
4:26 - Japan told the International Atomic Energy Association that "radioactivity was being released 'directly' into the atmosphere" from the nuclear site, Reuters reports.
2:09 - A U.S. scientists organization, the Union of Concerned Scientists, has speculated that the "radiation plume from a nuclear power plant damaged by Japan's devastating earthquake and subsequent tsunami could reach Tokyo," Reuters reports.
2:00 EST - "Government officials are considering a plan to use helicopters to drop water into the cooling pond through the damaged roof of the reactor building, according to a Kyodo News report." (via CNN). Winds are dispersing radiation over the Pacific ocean, and CBS News reports that U.S. military crews tested positive for low level radiation exposure while shuttling relief supplies to Japan.
Original Post: In the latest news from the damaged Fukushima Daiichi Nuclear Power Station, the panicked tones about an imminent meltdown have subsided with some reporting signs that radiation levels—which had led to warnings for people to stay in their homes—had stabilized and in some instances decreased.
The Associated Press reports that 140,000 people were ordered to seal themselves indoors after officials warned of potentially dangerous radiation levels. Late Monday night, The New York Times reported that Japanese authorities were warning anyone living within 30 km of the damaged to close their windows and not use air conditioning in an attempt to limit exposure to the increased threat of radiation leakage. Tepco (the Tokyo Electric Power Company) had withdrawn all but 50 of the 1,400 people working at the complex. On Tuesday morning, The Times observed "there were signs that workers, at least for the moment, contained some of the danger."
In a slightly more optimistic take, the Wall Street Journal reported that Japanese officials have now begun to stabilize "some aspects" of the problems at the plant, and radiation levels, "have dropped significantly from earlier in the day, ruling out the continuation of unstoppable large-scale leaks." The Journal, however, observed a new worry: "temperature at the remaining two reactors, both not operating at the time of the earthquake and so far not the subject of concern, has risen slightly, prompting the need for close monitoring."
Workers face a host of problems in trying to contain radioactive leakage from the six-reactor facility. "In addition to putting out the fire at unit 4, workers had found a way to stabilize troublesome units 1 and 3, keeping the fuel rods under the necessary cooling water," The Washington Post noted this morning.