Workers at Japan's Fukushima Daiichi nuclear power plant said they were "resigned to death" when the 9-magnitude quake struck on March 11.
One worker told NHK World he was working at unit 4 when he heard a "roar" and the lights cut out.
He said the water in the spent fuel storage pool drenched everyone.
"I thought I was going to die," he said through a translator.
On leaving the building, he saw white smoke coming out of the unit one reactor, which suffered a hydrogen explosion the next day.
Another man told NHK World of how he was having a nap in a corridor when part of the roof fell on him.
He said it was "chaos".
The man said he could not believe there was an explosion at unit 1 as he thought it was safe.
He said people working outside the reactors for only 15 minutes had levels of 10 millisieverts per hour which "terrified him", he said.
The man was evacuated after the blast at the number 3 reactor - but many stayed behind.
He said his "heart aches when he thinks of those that remain" and he "prays the situation will improve and they will be back as soon as possible".
Some progress seen in Japan's nuclear crisis
Meanwhile, Japanese officials have reported progress in their battle to gain control over a leaking, tsunami-stricken nuclear complex, though the crisis was far from over, with the discovery of more radiation-tainted vegetables and tap water adding to public fears about contaminated food and drink.
The announcement by Japan's Health Ministry late Sunday that tests had detected excess amounts of radioactive elements on canola and chrysanthemum greens marked a low moment in a day that had been peppered with bits of positive news: First, a teenager and his grandmother were found alive nine days after being trapped in their earthquake-shattered home. Then, the operator of the overheated nuclear plant said two of the six reactor units were safely cooled down.
"We consider that now we have come to a situation where we are very close to getting the situation under control," Deputy Cabinet Secretary Tetsuro Fukuyama said.
Still, serious problems remained at the Fukushima Daiichi nuclear complex. Pressure unexpectedly rose in a third unit's reactor, meaning plant operators may need to deliberately release radioactive steam. That has only added to public anxiety over radiation that began leaking from the plant after a monstrous earthquake and tsunami devastated northeastern Japan on March 11 and left the plant unstable. As day broke Monday, Japan's military resumed dousing of the complex's troubled Unit 4.
The safety of food and water was of particular concern. The government halted shipments of spinach from one area and raw milk from another near the nuclear plant after tests found iodine exceeded safety limits. But the contamination spread to spinach in three other prefectures and to more vegetables - canola and chrysanthemum greens. Tokyo's tap water, where iodine turned up Friday, now has cesium. Rain and dust are also tainted.
The Health Ministry also advised Iitate, a village of 6,000 people about 30 kilometres northwest of the Fukushima plant, not to drink tap water due to elevated levels of iodine. Ministry spokesman Takayuki Matsuda said iodine three times the normal level was detected there - about one twenty-sixth of the level of a chest X-ray.
In all cases, the government said the radiation levels were too small to pose an immediate health risk. But Taiwan seized a batch of fava beans from Japan found with faint - and legal - amounts of iodine and cesium.
"I'm worried, really worried," said Mayumi Mizutani, a 58-year-old Tokyo resident shopping for bottled water at a supermarket to give her visiting 2-year-old grandchild. "We're afraid because it's possible our grandchild could get cancer." Forecasts for rain, she said, were also a cause for concern.
All six of the nuclear complex's reactor units saw trouble after the disasters knocked out cooling systems. In a small advance, the plant's operator declared Units 5 and 6 - the least troublesome - under control after their nuclear fuel storage pools cooled to safe levels. Progress was made to reconnect two other units to the electric grid and in pumping seawater to cool another reactor and replenish it and a sixth reactor's storage pools.
But the buildup in pressure inside the vessel holding Unit 3's reactor presented some danger, forcing officials to consider venting. The tactic produced explosions of radioactive gas 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."
Nuclear safety officials said one of the options could release a cloud dense with iodine as well as the radioactive elements krypton and xenon.
The plant's operator, Tokyo Electric Power Co., temporarily suspended the plans Sunday after it said the pressure inside the reactor stopped climbing, though staying at a high level.
"It has stabilized," Tokyo Electric manager Hikaru Kuroda told reporters.
Kuroda, who said temperatures inside the reactor reached 300 degrees Celsius, said the option to release the highly radioactive gas inside is still under consideration if pressure rises.
Growing concerns about radiation add to the overwhelming chain of disasters Japan has struggled with since the 9.0-magnitude quake. It spawned a tsunami that ravaged the northeastern coast, killing 8,450 people, leaving more than 12,900 people missing, and displacing another 452,000, who are living in shelters.
Fuel, food and water remain scarce. The government in recent days acknowledged being caught ill-prepared by an enormous disaster that the prime minister has called the worst crisis since World War II.
Bodies are piling up in some of the devastated communities and badly decomposing even amid chilly rain and snow.
"The recent bodies - we can't show them to the families. The faces have been purple, which means they are starting to decompose," says Shuji Horaguchi, a disaster relief official setting up a center to process the dead in Natori, on the outskirts of the tsunami-flattened city of Sendai. "Some we're finding now have been in the water for a long time, they're not in good shape. Crabs and fish have eaten parts."
Before the disasters, safety drills were seldom if ever practiced and information about radiation exposure rarely given in Futuba, a small town in the shadow of the nuclear plant, said 29-year-old Tsugumi Hasegawa. She is living in a shelter with her 4-year-old daughter and feeling bewildered.
"I still have no idea what the numbers they are giving about radiation levels mean. It's all so confusing. And I wonder if they aren't playing down the dangers to keep us from panicking. I don't know who to trust," said Hasegawa, crammed with 1,400 people into a gymnasium on the outskirts of the city of Fukushima, 80km away from the plant.
Another nuclear safety official acknowledged that the government only belatedly realized the need to give potassium iodide to those living within 20 kilometres of the nuclear complex.
The pills help reduce chances of thyroid cancer, one of the diseases that may develop from radiation exposure, by preventing the body from absorbing radioactive iodine. The official, Kazuma Yokota, said the explosion that occurred while venting the plant's Unit 3 reactor a week ago should have triggered the distribution. But the order came only three days later.
"We should have made this decision and announced it sooner," Yokota told reporters at the emergency command center in Fukushima. "It is true that we had not foreseen a disaster of these proportions. We had not practiced or trained for something this bad. We must admit that we were not fully prepared."
The higher reactor pressure may have been caused by a tactic meant to reduce temperatures - the pumping of seawater into the vessel, said Kuroda, the Tokyo Electric manager.
Using seawater to cool the reactors and storage pools was a desperate measure adopted early last week; Unit 4's pool was sprayed again Sunday and a system to inject water into Unit 2's reactor was repaired. Experts have said for days that seawater would inevitably corrode and ruin the reactors and other finely milled machine parts, effectively turning the plant into scrap.
Edano, the government spokesman, recognized the inevitable Sunday: "It is obviously clear that Fukushima Daiichi in no way will be in a condition to be restarted."
Contamination of food and water compounds the government's difficulties, heightening the broader public's sense of dread about safety. Consumers in markets snapped up bottled water, shunned spinach from Ibaraki - the prefecture where the tainted spinach was found - and overall expressed concern about food safety.
Experts have said the amounts of iodine detected in milk, spinach and water pose no discernible risks to public health unless consumed in enormous quantities over a long time. Iodine breaks down quickly, after eight days, minimizing its harmfulness, unlike other radioactive isotopes such as cesium-137 or uranium-238, which remain in the environment for decades or longer.
High levels of iodine are linked to thyroid cancer, one of the least deadly cancers if treated. Cesium is a longer-lasting element that affects the whole body and raises cancer risk.
Rain forecast for the Fukushima area also could further localize the contamination, bringing the radiation to the ground closer to the plant.
Edano tried to reassure the public for a second day in a row. "If you eat it once, or twice, or even for several days, it's not just that it's not an immediate threat to health, it's that even in the future it is not a risk," Edano said. "Experts say there is no threat to human health."
No contamination has been reported in Japan's main food export - seafood - worth about $1.6 billion a year and less than 0.3 per cent of its total exports.
Amid the anxiety, there were moments of joy on Sunday. An 80-year-old woman and her teenage grandson were rescued from their flattened two-story house after nine days, when the teen pulled himself to the roof and shouted to police for help.
Other survivors enjoyed smaller victories. Kiyoshi Hiratsuka and his family managed to pull his beloved Harley Davidson motorcycle from the rubble in their hometown of Onagawa.
"I almost gave up the search but it happened that I found it," the 37-year-old mechanic said. "I know that the motorbike would not work anymore, but I want to keep it as a memorial."
- NZ Herald staff and AP