SENDAI, Japan -- A strong aftershock ripped through northeastern Japan, killing two people, knocking out power to vast areas Friday and piling misery on a region still buried under the rubble of last month's devastating tsunami.
The 7.1-magnitude tremor late Thursday was the strongest since northeastern Japan's jumbo 9.0-magnitude quake March 11. The latest shattered windows, kicked items from shelves and collapsed some roofs that weren't already demolished, but generated no tsunami and largely spared the region's nuclear plants. Some slightly radioactive water spilled at one plant, but the tsunami-crippled Fukushima Dai-ichi complex reported no new problems.
Matsuko Ito, who has been living in a shelter in the small northeastern city of Natori since the tsunami, said there's no getting used to the terror of being awoken by shaking. She said she started screaming when the quake struck around 11:30 p.m.
"It's enough," the 64-year-old while smoking a cigarette outside. "Something has changed. The world feels strange now. Even the way the clouds move isn't right."
Many people have lived without water and electricity for nearly a month, and the latest tremor sunk more homes into blackness: About 2.6 million households – about 40 percent of those supplied in the area – were dark Friday, said Souta Nozu, a spokesman for Tohoku Electric Power Co., which serves northern Japan.
Six conventional plants in the area were knocked out, though three have since come back online and the others should be up again within hours, Nozu said. But with power lines throughout the area damaged, it was not clear whether normal operations would be restored, he said.
Several nuclear power plants briefly switched to diesel generators but were reconnected to the grid by Friday afternoon. One plant north of Sendai – which has been closed since the tsunami – briefly lost the ability to cool its spent fuel pools, but quickly got it back.
At a plant in Onagawa, some radioactive water splashed out of the pools but did not leave a containment building, Tohoku Electric said. Such splash-out is "not unusual, although it is preferable that it doesn't happen," according to Japanese nuclear safety agency official Tomoho Yamada.
"Closer inspection could find more problems," said agency spokesman Hidehiko Nishiyama, but no radiation was released into the environment at Onagawa.
The plant began leaking oil into the ocean in the first earthquake, and the flow escaped a containment boom in Thursday's tremor, according to coast guard spokesman Hideaki Takase. By Friday, the leak had been contained again, he said.
Thursday's quake initiated a tsunami warning of its own, but it was later canceled. Two people were killed, national fire and disaster agency spokesman Junichi Sawada reported Friday. A 79-year-old man died of shock and a woman in her 60s was killed when power was cut to her oxygen tank. More than 130 people were injured, according to the national police agency.
That pales in comparison to the original quake and tsunami, in which more than 25,000 people are believed to have died.
Many of those bodies have still not been found: A significant portion were likely washed out to sea and never will be, but some are buried in areas that have been largely off-limits to search teams.
As radiation spilling from the troubled Fukushima Dai-ichi plant has fallen in recent days, however, police have fanned out inside a no-go zone near the complex to dig for the dead.
On Friday, hundreds of police, many mobilized from Tokyo, used their hands or small shovels, pulling four bodies in an hour from one small area in the city of Minami Soma. The had found only five bodies the previous day.
The searchers, wearing white radiation gear and blue gloves, struggled to bring the remains across the rubble to vans and minibuses that would take them to the nearest morgue. Each body was carefully hosed off to rid it of radiation before being placed in the vehicles.
"The area is literally a mountain of debris. It is an extremely difficult task," said an official with police in Fukushima prefecture who declined to be named because he was not authorized to talk to the media.
The epicenter of Thursday's temblor was in about the same location as the original 9.0-magnitude tremor, off the eastern coast and about 40 miles (65 kilometers) from Sendai, an industrial city on the eastern coast, according to the U.S. Geological Survey. It was strong enough to shake buildings for about a minute as far away as Tokyo, about 200 miles (330 kilometers) away.
At a Toyota dealership in Sendai, most of a two-story show window was shattered, and thick shards of glass were heaped in front of the building. Items fell off store shelves and a large automated teller machine crept across the floor at a FamilyMart convenience store.
Police directed cars through intersections throughout the city on Friday because traffic lights were out. Small electrical fires were reported.
While the city is far enough inland that it largely escaped tsunami damage, people there lived without regular services for weeks. Within an hour of Thursday's quake, they rushed convenience stores and cleared shelves of ice, water and instant noodles – items that were in short supply after the bigger quake.
The operator of the tsunami-ravaged Fukushima Dai-ichi plant said there was no sign the aftershock had caused new problems there. Workers briefly retreated to a quake-resistant shelter in the complex and suffered no injuries.
After the March 11 quake knocked out power in the region, the wave flooded the plant's diesel generators, leaving the complex without any electricity. Workers have been struggling to stem a tide of radiation since, using makeshift methods to pump cooling water into the reactors. That work continued uninterrupted after the latest quake, according to Japan's Nuclear and Industrial Safety Agency.
Associated Press writers Shino Yuasa, Malcolm Foster, Ryan Nakashima, Mari Yamaguchi and Cara Rubinsky in Tokyo, Eric Talmadge in Minami Soma, and Colleen Slevin in Denver contributed to this report.