Japan Quake Kills at Least 6 and Injures Hundreds

By NORIMITSU ONISHI

TOKYO, July 16 — A powerful earthquake shook Japan’s northwestern coast this morning, killing seven people and injuring more than 700, flattening hundreds of buildings and leaving thousands homeless.

The earthquake also sparked a fire at a nuclear power plant, which later leaked a small amount of water containing radioactive materials into the sea. The company operating the plant said the radioactivity level posed no danger to the environment.

The earthquake, whose strength was estimated at 6.8 on the Richter scale, was centered off the cost of Niigata, a prefecture that was hit by a devastating earthquake in 2004. Skyscrapers in Tokyo, about 130 miles southeast of Niigata, swayed for almost a minute from the tremor.

The earthquake, which occurred at 10:13 a.m. on a day that is a national holiday in Japan, caused minor tsunamis and buckled roads and bridges in the region. It toppled one local train off its rails, and caused the shutdown of service on a high-speed intercity “bullet train” line for several hours. Power and water supplies were cut off to tens of thousands of homes.

Nuclear reactors at power plants were shut down automatically, but the quake caused a small fire at an electrical transformer at a nuclear plant in Kashiwazaki, a coastal town close to the quake’s epicenter. Japanese television stations showed flames and black smoke billowing from the facility, which is operated by Tokyo Electric and is the world’s largest nuclear plant.

Tokyo Electric said initially said that there was no radiation leak at the plant. But later in the evening, it said in a statement that 1.5 liters (a bit less than three pints) of water water containing low levels of radioactive material leaked into the Sea of Japan from two locations at its No. 6 reactor.

The leaks occurred at about 12:50 p.m., but the company was not certain five and a half hours later that the water was radioactive, the statement said.

More than 7,000 people in the quake-affected region have left their homes for evacuation centers, according to NHK, the public broadcaster.

Aftershocks could be felt for several hours after the quake, including a large one at 3:37 p.m. that was as far away as Tokyo. News agencies reported an aftershock late in the evening that was nearly as strong as the main quake.

Prime Minister Shinzo Abe interrupted a campaign appearance in Nagasaki, in western Japan, to fly by helicopter to Niigata.

“I would like to make every possible effort to restore lifelines such as roads, gas and water, because the victims are in a tough situation,” Mr. Abe told reporters after surveying some damaged areas. Mr. Abe’s approval ratings have been sliding in recent weeks, in the run-up to an election for seats in the upper house of parliament near the end of this month.

Troops from the Japanese army, known as the Self-Defense Force, were sent to the affected area to help with rescue and relief work. In Kashiwazaki, troops succeeded in freeing an elderly woman who had been trapped in the rubble of her home for more than five hours.

Officials said the seven deaths from the earthquake were men and women in their 70’s and 80’s. Like other rural areas in Japan, Niigata has a disproportionately large number of elderly residents, many of them living alone in older wooden houses.

In early 2006, record snowfalls in Niigata trapped many elderly indoors or forced able-bodied septuagenarians and octogenarians onto their roofs to shovel snow. Many died.

In October 2004, more than 60 people died and thousands were injured in a 6.8-magnitude earthquake that hit Niigata. The government was criticized for not providing adequate services for evacuees, many of whom had to stay in public facilities for months.