A strong earthquake jolted northwestern Japan on Monday, injuring more than 190 people, destroying houses and sparking a fire at a nuclear power plant, Japanese media and officials said.
"I was on the street, and there was strong sideways shaking. I couldn't remain standing. One wall has collapsed," gasoline station worker Hiroki Takahashi told public broadcaster NHK in Kashiwazaki City, near the focus of the quake, where television reported at least 12 people were trapped under collapsed houses.
One person was in critical condition after being pulled from a collapsed building, media said, but there were no initial reports of deaths from the magnitude 6.8 tremor, centered some 250 km (155 miles) northwest of Tokyo.
Several houses collapsed and a temple's roof caved in, television pictures showed. Buildings swayed in Tokyo, and nuclear power reactors in Niigata prefecture were shut down for checks but there were no radiation leaks reported.
Black smoke billowed from a fire in an electrical transformer building at the Kashiwazaki Kariwa nuclear power plant near the epicenter. The fire was largely out by noon. Bullet trains to the area were halted briefly and local trains stopped. TV pictures showed one train had fallen off the rails.
The 10:13 a.m. Tokyo time quake with a magnitude of 6.8 was centered around 60 km (37 miles) southwest of Niigata, revised upwards from a preliminary 6.6 magnitude.
Prime Minister Shinzo Abe had cut short campaigning for an upcoming Upper House election and was returning to Tokyo, Chief Cabinet Secretary Yasuhisa Shiozaki told a news conference. The government had established an emergency office to deal with the quake, he added.
Monday is a holiday in Japan so financial markets were closed.
"Gas seems to have leaked in some places. Electricity is fine, but I can't go inside," Kashiwazaki resident Masae Yanai told public broadcaster NHK.
Tsunami warning sirens sounded along affected stretches of the Sea of Japan, with a surge of up to about 50 cm (20 inches) predicted, but the warning was later withdrawn.
Niigata was the site of an October 2004 earthquake with a matching magnitude of 6.8 that killed 65 people and injured more than 3,000. That was the deadliest quake since a magnitude 7.3 tremor hit the city of Kobe in 1995, killing more than 6,400.