It is seen as a desperate measure in the battle to prevent a full meltdown at the Fukushima nuclear power plant on Japan's east coast. On Thursday morning, two Chinook military helicopters dumped seawater on the stricken reactors on Thursday to cool spent fuel rods that are normally stored in pools of deep water.

Videos show the helicopters dunking giant red canisters into the ocean and emptying them over the power plant, distributing the water like an enormous sprinkler system. A similar effort had been called off on Wednesday due to high levels of radiation measured over the plants.

The Chinook sorties belonged to a wider emergency plan to keep the reactor and the store of spent rods in the plant's Unit 3 from releasing mass quantities of radiation. Already, steam releases and a trio of blasts at the site have resulted in severe radiation leaks. And on Wednesday, an American official voiced concern during Congressional testimony that the amount of radiation released has actually been much higher than that acknowledged by Japanese authorities.

Indeed, on Thursday it appeared that high levels of radiation were hampering efforts by workers to get close enough to Unit 3 to deploy water cannon to spray the site. The effect of the dousing efforts were not immediately clear. The Japanese government has said that a reactor typically needs about 12,000 gallons of water a day to prevent overheating. The Chinook helicopters were able to dump 8,000 gallons.

Skeleton Crew

Thursday's efforts appeared to be largely focused on Unit 3. But three other reactors at the facility are likewise facing serious problems, with radiation leaks from reactor 4 having been the focus of Wednesday's Congressional testimony. A small glimmer of hope could be provided by an emergency power line, expected to be completed late Thursday, which could restore power to reactor cooling systems.

The Tokyo Electric Power Company (TEPCO), which runs the facility, has called for 20 volunteers to return to Fukushima Dai-ichi to assist in the desperate efforts. Earlier this week, a skeleton crew of 50 to 70 personnel stayed behind after most of the staff went home because of radiation hazards. A number of workers have returned voluntarily, including a man with decades of experience who was ready to retire, the Japanese news agency Jiji reported Thursday.

Cooling systems at Fukushima Dai-ichi and several other nuclear plants failed after a tsunami on Friday, which in turn resulted from an unprecedented 9.0 earthquake centered just off the east coast of northern Honshu, Japan's main island. National TV broadcaster NHK places the overall death toll at 5,200, but at least 9,000 people remain missing. Hundreds of thousands have lost their homes.

'Apocalyptic Dimension'

German Chancellor Angela Merkel promised aid to Japan in a statement in Berlin on Thursday morning. "The catastrophe in Japan has a downright apocalyptic dimension," she said, and expressed "horror, astonishment, compassion and grief," on behalf of Germany. "The outcome of this catastrophe is not yet predictable at all," she added.

Flood damage by the tsunami, evacuations around power plants, snow, and blackouts have led to chaos on Japan's northeastern coast. In the town of Ofunato, in the Iwate prefecture, people sheltered in a candle-lit gymnasium at a local elementary school. Some 400 locals spent Tuesday night there, shivering under thin wool blankets.

"I only slept three hours, because it was so cold," said Yotsuko Tanaka, a 72-year-old woman who lost her home to the tsunami on Friday, according to the Mainichi Daily News. The earthquake -- the largest on record to hit Japan and among of the largest ever measured -- has delivered numerous aftershocks, some of them in the 6.0 range, which on their own would qualify as large quakes.

"Every time the earth moves, my daughter lies flat on the floor and cries that she's afraid of another tsunami," said Hiromi Yamamoto, also according to the Mainichi Daily News. She saved herself and her 3-year-old daughter from the deadly wave on Friday.

Time Running Short

The search for survivors and bodies in the still-flooded streets of Ofunato has proved grim. "The strong smell of bodies and the dirty sea water make search extremely difficult, said Yin Guanghui, a member of a Chinese rescue team, according to the Associated Press.

The hardest-hit areas of northeastern Japan include the Iwate, Miyagi and Fukushima prefectures, where official death tolls may exceed 10,000 by the end of this week, according to local authorities. More than 440,000 people have been evacuated, some 850,000 households lack electricity in the near-freezing weather, and about 1.5 million households lack running water, according to government and power company sources.