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KASHIWAZAKI, Japan - A strong earthquake killed at least four people in Japan on Monday, injured more than 400, flattened houses and started a small fire at the world's largest nuclear power plant, Japanese media and officials said.
Two women in their 80s died when their homes collapsed due to the magnitude 6.8 tremor, centred in Niigata prefecture some 250 km northwest of Tokyo, Japanese media said.
Details of the other two deaths, reported by public broadcaster NHK, were not immediately available.
"It was too strong to stand. Some people got under tables, others immediately went outside," said police officer Masao Honma in Kashiwazaki City, near the focus of the quake, where there were reports of at least 12 people trapped in collapsed houses.
"It's really rough," Honma told Reuters by phone.
Houses, many wooden with traditional heavy tile roofs, were flattened, a temple roof caved in and roads cracked in the quake, which was centred in the same northwestern area as a tremor three years ago that killed 65 people.
Nearly 100 evacuation centres were being set up, a Niigata Prefecture official said, and troops and extra emergency teams were being sent to help with rescue and relief efforts.
"It brought back memories of the previous quake," a middle aged woman told television from her home, where furniture had been toppled and belongings were scattered around.
Buildings swayed as far away as Tokyo, and nuclear power reactors in Niigata prefecture automatically shut down for checks but there were no radiation leaks reported.
A fire in an electrical transformer at the Kashiwazaki Kariwa nuclear power plant -- the world's largest -- was quickly extinguished but it was unclear when Tokyo Electric Power Co (TEPCO) could restart three power units there, Yoshinobu Kamijima, a company spokesman said.
Japan is one of the world's most earthquake-prone countries, with a tremor occurring at least every five minutes.
Prime Minister Shinzo Abe cut short campaigning for an upcoming Upper House election and returned to Tokyo, where the government established an emergency office to deal with the quake that officials said had damaged some 350 buildings.
"We need to take every step to save lives. It's supposed to rain tomorrow in the area so we have to take every step to save lives, secure lifelines and reassure people," Abe told reporters, adding he would visit the affected area.
Bullet trains in northern Japan were halted briefly and local trains stopped. A local train toppled off the rails, but media said no one was injured.
Power and gas were cut to many homes and public broadcaster NHK said some 37,000 households had lost water supplies.
"We have a water tank for two days, but the city called to say they don't know when water will be running again," said Reiko Nakao, who works at a hotel in Kariwa village.
"Dishes and a TV fell off our shelves with the shaking. We haven't checked the outside wall yet, but there are cracks in the pavement around the hotel."
The 10:13am local time quake was centred around 60 km southwest of Niigata. Monday is a holiday in Japan so financial markets were closed.
Tsunami warning sirens sounded along affected stretches of the Sea of Japan but the warning was later withdrawn.
Niigata was hit in October 2004 by a quake with a matching magnitude of 6.8 that killed 65 people and injured more than 3,000. That was the deadliest quake in Japan since a magnitude 7.3 tremor hit the city of Kobe in 1995, killing more than 6,400.
Sanyo Electric Co. spokesman Akihiko Oiwa said operations at a semiconductor factory in Niigata, one of the firm's largest, had been halted but there had been no reports of damage.
- REUTERS
