A long list of problems, including radiation leaks, burst pipes and fire, have come to light at the world's largest nuclear power plant after it was hit by a powerful earthquake this week.
The malfunctions and a delay in reporting them following Monday's 6.8-magnitude temblor fueled concerns about the safety of Japan's 55 nuclear reactors, which have suffered a string of accidents and cover-ups.
"They raised the alert too late. I have sent stern instructions that such alerts must be raised seriously and swiftly," Prime Minister Shinzo Abe told reporters in Tokyo on Tuesday. "Those involved should think seriously about their actions."
Kashiwazaki-Kariwa is the world's largest nuclear plant in power output capacity. Japan's nuclear plants supply about 30 percent of the country's electricity, but its dependence on nuclear power is coupled with deep misgivings over safety.
The power plant suffered broken pipes, water leaks and spills of radioactive waste when it was hit by the earthquake Monday, the plant's operator said.
Signs of problems, however, came first not from the officials, but in a plume of smoke that rose up when the quake triggered a small fire at an electrical transformer.
It was announced only 12 hours later that the magnitude 6.8 temblor also caused a leak of about 315 gallons of water containing radioactive material. Officials said the water leak was well within safety standards. The water was flushed into the sea.
The company also said a small amount of radioactive materials cobalt-60 and chromium-51 had been emitted into the atmosphere from an exhaust stack.
Later Tuesday, it said 50 cases of "malfunctioning and trouble" had been found. Four of the plant's seven reactors were running at the time of the quake, and they were all shut down automatically by a safety mechanism.
Officials said there was no harm to the environment, but acknowledged it took a day to discover about 100 drums of low-level nuclear waste that were overturned, some with the lids open.
Kensuke Takeuchi, a spokesman for Tokyo Electric Power Co., which runs the plant, called the malfunctions "minor troubles."
Across town, more than 8,000 residents hunkered down for their second night in shelters. The death toll -- nine, with one person missing -- was not expected to rise significantly. Most of the newer parts of town escaped major damage.
For residents, thousands of whom work at the plant, the controversy over its safety compounded already severe problems, which included heavy rains and the threat of landslides, water and power outages, and spotty communications.
"Whenever there is an earthquake, the first thing we worry about is the nuclear plant. I worry about whether there will be a fire or something," said Kiyokazu Tsunajima, a tailor who sat outside on his porch with his family, afraid an aftershock might collapse his damaged house.
"It's frightening, but I guess we are used to it," said Ikuko Sato, a young mother who was spending the night in a crowded evacuation center near her home, which was without water or power. "It's almost the summer swimming season," she said. "I wonder if it'll be safe to go in the water."
The area around Kashiwazaki was hit by an earthquake three years ago that killed 67 people, but the plant suffered no damage.
Economy, Trade and Industry Minister Akira Amari told TEPCO it must not resume operations at the plant until it has made a thorough safety check. Nuclear power plants around Japan were ordered to conduct inspections.
The plant in Kashiwazaki-Kariwa, 220 kilometers (135 miles) northwest of Tokyo, eclipsed a nuclear power station in Ontario as the world's largest power station when it added its seventh reactor in 1997.
The Japanese plant, which generates 8.2 million kilowatts of electricity, has been plagued with mishaps. In 2001, a radioactive leak was found in the turbine room of one reactor.
The plant's safety record and its proximity to a fault line prompted residents to file lawsuits claiming the government had failed to conduct sufficient safety reviews when it approved construction of the plant in the 1970s. But in 2005, a Tokyo court threw out a lawsuit filed by 33 residents, saying there was no error in the government safety reviews.
Environmentalists have criticized Japan's reliance on nuclear energy as irresponsible in a nation with such a vulnerability to powerful quakes.
"This fire and leakage underscores the threat of nuclear accidents in Japan, especially in earthquake zones," said Jan Beranek, a Greenpeace official in Amsterdam. "In principle, it's a bad idea to build nuclear plants in earthquake-prone areas.