Japan's nuclear crisis appeared to be spinning out of control on Wednesday after workers withdrew briefly from a stricken power plant because of surging radiation levels and a helicopter failed to drop water on a second reactor that may have ruptured.
In a sign of desperation, crews planned to try to cool spent nuclear fuel at one of the facility's reactors with water cannons, normally used to quell riots.
Early in the day, another fire broke out at the earthquake-crippled facility, which has sent low levels of radiation wafting into Tokyo, triggering fear in the capital and international alarm.
Japan's government said radiation levels outside the plant's gates were stable but appealed to private companies to help deliver supplies to tens of thousands of people evacuated from around the complex.
"People would not be in immediate danger if they went outside with these levels. I want people to understand this," Chief Cabinet Secretary Yukio Edano told a televised news conference, referring to people living outside an 18-mile exclusion zone. Some 140,000 people inside the zone have been told to stay indoors.
The European Union's energy chief, Guenther Oettinger, told the European Parliament that the plant was "effectively out of control" after breakdowns in the facility's cooling system.
"In the coming hours there could be further catastrophic events, which could pose a threat to the lives of people on the island," Oettinger said.
"There is as yet no panic, but Tokyo with 35 million people, is the largest metropolis in the world," he said.
The U.N. atomic watchdog chief took issue with Oettinger's comments.
"It is not the time to say things are out of control," Yukiya Amano, director general of the International Atomic Energy Agency, told a news conference when asked about the comments. "The operators are doing the maximum to restore the safety of the reactor."
Amano said he hoped to fly to Japan Thursday for a one-day trip and needed more information from authorities there. He earlier urged the Japanese government to provide better information to the IAEA about the crisis.
A Pentagon spokesperson said that all U.S. forces operating in Japan must now stay at least 50 miles from the Fukushima plant, unless they have special approval to be closer.
This decision comes amid the revelation that several more U.S. Navy air crew members tasked with flying within 70 nautical miles of Fukushima were given potassium iodide tablets Wednesday. The measures were seen as precautions, and the Pentagon said no U.S. forces have shown signs of radiation poisoning.
Meanwhile, workers cleared debris to build a road so fire trucks could reach reactor No. 4 at the Daiichi complex in Fukushima, 150 miles north of Tokyo. Flames were no longer visible at the building housing the reactor.
High radiation levels prevented a helicopter from dropping water into the No. 3 reactor to try to cool its fuel rods after an earlier explosion damaged the unit's roof and cooling system.
The plant operator described No. 3 — the only reactor at that uses plutonium in its fuel mix — as the "priority." Plutonium, once absorbed in the bloodstream, can linger for years in bone marrow or liver and lead to cancer.
The reactor unit may have ruptured, although officials said the damage was unlikely to be severe.
The situation at No. 4 reactor, where the fire broke out, was "not so good", the plant operator TEPCO added, while water was being poured into reactors No. 5 and 6, indicating the entire six-reactor facility was now at risk of overheating.
"Getting water into the pools of the No. 3 and No. 4 reactors is a high priority," Hidehiko Nishiyama, a senior official at Japan's Nuclear and Industrial Safety Administration, told a news conference, adding the pool for spent fuel rods at No. 3 was heating up while No. 4 remained a concern.
"It could become a serious problem in a few days," he said.
A military helicopter may be used again to try to drop water and troops mobilized to help pump water by land, he said.
Nuclear experts said the solutions being proposed to quell radiation leaks at the complex were last-ditch efforts to stem what could well be remembered as one of the world's worst industrial disasters.
"This is a slow-moving nightmare," said Thomas Neff, a physicist and uranium-industry analyst at the Massachusetts Institute of Technology.
The Pentagon was sending more equipment to help Japan control the stricken reactors.
Several water pumps were being sent from U.S. bases around Japan, and the U.S. had already sent two fire trucks to the area to be operated by Japanese firefighters, said Cmdr. Leslie Hull-Ryde, a Pentagon spokeswoman.
U.S. military assistance so far has focused on delivering relief supplies and helping with logistics and search and rescue missions.
However, pilots could not fly helicopters off the deck of aircraft carrier USS Ronald Reagan until late afternoon Wednesday because of poor visibility.
The 7th Fleet said that only 15 flights with relief supplies were launched from the eight-ship carrier group, about half as many as the 29 flights reported the previous day to deliver food, water, blankets and other supplies.
Meanwhile, Japanese Emperor Akihito, delivering a rare video message to his people, said he was deeply worried by the country's nuclear crisis which was "unprecedented in scale."
$200 billion losses feared
Panic over the economic impact of last Friday's massive earthquake and tsunami knocked $620 billion off Japan's stock market over the first two days of this week, but the Nikkei index rebounded on Wednesday to end up 5.68 percent.
Nevertheless, estimates of losses to Japanese output from damage to buildings, production and consumer activity ranged from between $125 billion and $200 billion, up to one-and-a-half times the economic losses from the devastating 1995 Kobe earthquake.
Damage to Japan's manufacturing base and infrastructure is also threatening significant disruption to the global supply chain, particularly in the technology and auto sectors.
Scores of flights to Japan have been halted or rerouted and air travelers are avoiding Tokyo for fear of radiation.
On Wednesday, both France and Australia urged their nationals in Japan to leave the country as authorities grappled with the world's most serious nuclear accident since the Chernobyl disaster in Ukraine in 1986.
Russia said it planned to evacuate families of diplomats on Friday.
Serbia and Croatia advised their citizens to leave Japan, while Croatia said it was moving its embassy from Tokyo to Osaka because of the nuclear crisis.
More than 3,000 Chinese have already been evacuated from Japan's northeast to Niigata on Japan's western coast, according to Xinhua News Agency.
U.S. Ambassador to Japan John Roos briefed reporters Wednesday, saying American officials were carefully monitoring radiation levels.
"If we assess that the radiation poses a threat to public health, we will share that information and provide relevant guidance immediately," Roos said.
In a demonstration of the qualms about nuclear power that the crisis has triggered around the globe, China announced that it was suspending approvals for planned plants and would launch a comprehensive safety check of facilities.
China has about two dozen reactors under construction and plans to increase nuclear electricity generation about seven-fold over the next 10 years.
At the Fukushima plant, authorities have spent days desperately trying to prevent water designed to cool the radioactive cores of the reactors from evaporating, which would lead to overheating and possibly a dangerous meltdown.
Until the heightened alarm about No. 3 reactor, concern had centered on damage to a part of the No.4 reactor building, where spent rods were being stored in pools of water, and also to part of the No. 2 reactor that helps to cool and trap the majority of cesium, iodine and strontium in its water.
Concern has mounted that the skeleton crews dealing with the crisis might not be big enough or were exhausted after working for days since the earthquake damaged the facility.
Authorities withdrew 750 workers for a time on Tuesday, briefly leaving only 50.
All those remaining were pulled out for almost an hour on Wednesday because radiation levels were too high, but they were later allowed to return.
By the end of the day, about 180 were working at the plant.