Last updated 10:00 p.m. ET
Two units at Japan's stricken nuclear plant have cooled down enough to be declared under control, though pressure unexpectedly rose in a third unit's reactor.
The plant operator, Tokyo Electric Power Company, says Units 5 and 6 are safe after days of pumping water into their fuel storage pools.
But the two units are the least problematic of the six reactor units at the Fukushima Dai-ichi nuclear complex. The units began overheating and releasing radiation into the air after the earthquake-triggered tsunami disrupted the plant's cooling systems.
Seawater is being pumped in to cool another reactor and replenish fuel storage pools. And workers are said to be making progress in their efforts to reconnect two other units to the electric grid.
The pressure increase meant plant operators may need to deliberately release radioactive steam, prolonging a nuclear crisis that has consumed government attention even as it responded to the catastrophic earthquake and tsunami that savaged northeast Japan on March 11.
However, TEPCO told reporters Sunday that plan was temporarily suspended after it the pressure inside the reactor stopped climbing, though at a high level.
"It has stabilized," Tokyo Electric manager Hikaru Kuroda told reporters.
Kuroda, who said temperatures inside the reactor reached 572 Fahrenheit degrees, said the option to release the highly radioactive gas inside is still under consideration if pressure rises.
In a rare rescue after so many days, a teenage boy's cries for help led police to rescue him and an 80-year-old woman at a wrecked house.
Beyond the disaster area, an already shaken public grew uneasy with official reports that traces of radiation first detected in spinach and milk from farms near the nuclear plant are turning up farther away in tap water, rain and even dust. In all cases, the government said the radiation levels were too small to pose an immediate risk to health. Still, Taiwan seized a batch of fava beans from Japan found with faint -- and legal -- amounts of iodine and cesium.
All six of the Fukushima Dai-ichi nuclear complex's reactor units saw trouble after the disasters knocked out cooling systems. But officials reported headway this weekend in reconnecting at least one unit to the electric grid and in pumping seawater to cool reactors and replenish bubbling or depleted pools for spent nuclear fuel.
But the buildup in pressure inside the vessel holding Unit 3's reactor renewed the danger, forcing officials to consider venting. The tactic produced explosions during the early days of the crisis.
"Even if certain things go smoothly there would be twists and turns," Chief Cabinet Secretary Yukio Edano told reporters. "At the moment, we are not so optimistic that there will be a breakthrough."
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