KASHIWAZAKI, Japan - A strong earthquake shook Japan's northwest coast Monday, setting off a fire at the world's most powerful nuclear power plant and causing a reactor to spill radioactive water into the sea - an accident not reported to the public for hours.
The 6.8-magnitude temblor killed at least 8 people and injured more than 900 as it toppled hundreds of wooden homes and tore 3-foot-wide fissures in the ground. Highways and bridges buckled, leaving officials struggling to get emergency supplies into the region.
Some 10,000 people fled to evacuation centers as aftershocks rattled the area. Tens of thousands of homes were left without water or power.
The quake triggered a fire in an electrical transformer and also caused a leak of radioactive water at the Kashiwazaki Kariwa nuclear power plant, the world's largest in terms of electricity output.
The leak was not announced until the evening, many hours after the quake. That fed fresh concerns about the safety of Japan's 55 nuclear reactors, which supply 30 percent of the quake-prone country's electricity and have suffered a long string of accidents and cover-ups.
About 315 gallons of slightly radioactive water apparently spilled from a tank at one of the plant's seven reactors and entered a pipe that flushed it into the sea, said Jun Oshima, an executive at Tokyo Electric Power Co. He said it was not clear whether the tank was damaged or the water simply spilled out.
Officials said there was no 'significant change' in the seawater near the plant, which is about 160 miles northwest of Tokyo. 'The radioactivity is one-billionth of the legal limit,' Oshima said of the leaked water.
Eliot Brenner, a spokesman for the U.S. Nuclear Regulatory Commission in Washington, said the agency told Japan's government it was ready to provide assistance if needed but had not received any request for help.
Brenner said he didn't have details about the incident. But a U.S. nuclear industry official, who spoke on condition of anonymity because the incident was a Japanese affair, said the transformer fire and water leak occurred in systems linked to different reactors.
In Kashiwazaki city, the quake reduced older buildings to piles of lumber. Eight people in their 70s and 80s - five women and three men - died, most of them crushed by collapsing buildings, the National Police Agency said.
Kyodo News agency reported more than 900 people were hurt, with injuries including broken bones, cuts and bruises. It said 780 buildings sustained damage, and more than 300 of them were destroyed.