Panic swept Tokyo on Tuesday after a rise in radioactive levels around an earthquake-hit nuclear power plant north of the city, causing some residents to leave the capital and others to stock up on food and supplies.
Several embassies advised staff and citizens to leave affected areas, tourists cut short vacations and multinational companies either urged staff to leave or said they were considering plans to move outside Tokyo.
In one sign of the panic, Don Quixote, a multistorey, 24-hour general store in Tokyo's Roppongi district, was sold out of radios, torches, candles, fuel cans and sleeping bags on Tuesday as a Reuters reported visited the shop.
Tourists such as Christy Niver, of Egan, Minnesota, said they had enough and were leaving. Her 10-year-old daughhter Lucy was more emphatic. "I'm scared. I'm so scared I would rather be in the eye of a tornado," she said. "I want to leave."
The Czech Symphony Orchestra left Tokyo by bus for Ishikawa prefecture on Japan's west coast after their concert in Tokyo was cancelled.
"Some of them wanted to go home after the earthquake, but it's pretty much impossible to get tickets for a hundred people now," said Hitomi Sakuma, a pianist who is friends with the orchestra and was seeing them off at a Tokyo hotel.
U.S. banking giant Citigroup said it was keeping workers constantly informed of the situation, but that there were no current evacuation orders from headquarters, said a spokesman, adding that the bank was closely following guidance by the U.S. embassy, which has not urged nationals to leave Tokyo.
Some international journalists covering the disaster from the worst-hit region around the northeastern city of Sendai, devastated by Friday's mammoth earthquake and tsunami that killed at least 10,000, were pulling out.
The Tokyo office of Michael Page International, a British recruitment agency, was closing for the week. "I am leaving for Singapore tomorrow and will work from our Singapore office," said one employee.
Kyodo News said "minute levels" of radiation have been detected in Tokyo and radiation levels in Saitama, near Tokyo, were 40 times normal levels -- not enough to cause human damage but enough to stoke panic in the bustling, ultra-modern and hyper-efficient metropolis of about 12 million people.
Winds over the troubled Fukushima Daiichi nuclear-power complex, about 240 km (150 miles) north of Tokyo, are blowing slowly in a southwesterly direction that includes Tokyo, but will shift westerly later on Tuesday, a weather official said.
The wind is moving at a speed of about two to three metres (7 to 10 ft) per second, said the official with the Japan Meteorological Agency who is based in Fukushima Prefecture, the location of three troubled reactors.
STRANDED AIRLINE PASSENGERS
Yoshiyuki Sakuma, a musician who lives in Yashio city in Saitama prefecture, just north of Tokyo, lamented that he couldn't buy any rice, a staple of Japanese households.
"I couldn't find any anywhere," he said, showing a photo on his cell phone that he took of a wide swath of bare shelves at a large supermarket near his home, adding that he was now searching for bread.
"If you lose electricity, water and gas, at least you can still eat bread," he said.
The French embassy in Tokyo warned in an 0100 GMT advisory that a low level of radioactive wind could reach Tokyo in about 10 hours, advising its citizens to leave the city.
The German embassy issued a "general advisory" urging all Germans and their relatives to register on a "crisis list" and to consider leaving Japan, especially those with families.
Some urged an expansion in the 30 km (18 km) evacation zone surrounding the plant.
"The evacuation zone may not be enough," said a Hiroshima-based Japanese scientist who treats nuclear radiation victims.
"The main lasting effect will probably be in milk produce and the radiation in milk, because the cows go around like vacuum cleaners and absorb the radiation spread over a wide range and those particles are easily transferred into the milk, which is in turn easily absobed by babies and children."
The number of stranded passengers swelled at Tokyo's main international airport at Narita as airlines cut flights.
"The airport appears crowded due to the stranded passengers, but we have not experienced a surge in passenger traffic," said a Narita official. "Of the 534 flights scheduled yesterday, 27 were cancelled and five were delayed for the next day. So traffic is not rising."
China's national airline cancelled flights to Tokyo on Tuesday after reports that low-level radioactive wind from a damaged nuclear reactor could reach the city later in the day, but other carriers they were still monitoring the situation.
Air China did not give a reason for the cancellations of flights from Beijing and Shanghai to Tokyo. Singapore Airlines , Cathay Pacific, Air New Zealand and several other airlines said they were monitoring the situation but had not cancelled any services to Tokyo.
Earlier, Japan's prime minister warned that radioactive levels had become high around the nuclear power plant after explosions at two reactors, adding that the risk of more radioactive leakage was rising.
There have been a total of four explosions at the plant since it was damaged in last Friday's massive earthquake and tsunami.
The fear at the Fukushima plant is of a major radiation leak after the quake and tsunami knocked out cooling systems.
The worst nuclear accident since the Chernobyl disaster in Ukraine in 1986 has drawn criticism that authorities were ill-prepared, and revived debate in many countries about the safety of atomic power.