TOKYO (AP) - Japan's northeastern coast was a swampy wasteland of brokenhouses, overturned cars, sludge and dirty water Saturday as thenation awoke to the devastating aftermath of one of its greatestdisasters, a powerful tsunami created by one of the strongestearthquakes ever recorded.
The death toll from Friday's massive magnitude 8.9 quake stoodat more than 200, but an untold number of bodies were believed tobe lying in the rubble and debris, and Japanese were bracing formore bad news as authorities tried to reach the hardest-hitareas.
Aerial footage showed military helicopters lifting people onrescue tethers from rooftops and partially submerged buildingssurrounded by water and debris. At one school, a large white "SOS"had been spelled out in English.
The earthquake that struck off the northeastern shore was thebiggest recorded quake ever to hit Japan. It ranked as thefifth-largest earthquake in the world since 1900 and was nearly8,000 times stronger than one that devastated Christchurch, NewZealand, last month, scientists said.
Chief Cabinet Secretary Yukio Edano said an initial assessmentfound "enormous damage," adding that the Defense Ministry wassending troops to the hardest-hit region.
The official casualty toll was 236 dead, 725 missing and 1,028injured, although police said 200-300 bodies were found along thecoast in Sendai, the biggest city in the area. Authorities saidthey weren't able to reach the area because of damage to theroads.
Black smoke could still be seen in the skies around Sendai,presumably from gas pipes snapped by the quake or tsunami.
Early Saturday morning, Atsushi Koshi, a 24-year-old call centerworker in the coastal city of Tagajo, about 10 miles (16kilometers) east of Sendai, said his cousin remained trapped on theroof of a department store with about 200 to 300 other peopleawaiting rescue. The store wasn't far from the port of Sendai,where the tsunami had washed ashore.
The rest of his family was safe, but he wondered what to do,since the house he shares with his parents was tilting from thequake and a concrete block wall had fallen apart.
"If we clean up our house it might be livable, but we'rediscussing what to do next," he said.
The quake shook dozens of cities and villages along a 1,300-mile(2,100-kilometer) stretch of coast and tall buildings swayed inTokyo, hundreds of miles from the epicenter. Minutes later, theearthquake unleashed a 23-foot (seven-meter) tsunami that washedfar inland over fields and smashed towns.
The town of Rikuzentakada, population 24,700, in northern Iwateprefecture, looked largely submerged in muddy water, with hardly atrace of houses or buildings of any kind.
The entire Pacific had been put on alert - including coastalareas of South America, Canada and Alaska - but waves were not asbad as expected.
The U.S. Geological Survey said that after the initial hugequake, there were 123 aftershocks off Japan's main island ofHonshu, 110 of them of magnitude 5.0 or higher
President Barack Obama pledged U.S. assistance following what hecalled a potentially "catastrophic" disaster. He said one U.S.aircraft carrier is already in Japan and a second was on its way. AU.S. ship was also heading to the Marianas Islands to assist asneeded, he added.
Japan also declared its first-ever states of emergency for fivenuclear reactors at two power plants after the units lost coolingability in the aftermath of the earthquake, and workers struggledto prevent meltdowns.
The earthquake knocked out power at the Fukushima Daiichi plant,and because a backup generator failed, the cooling system wasunable to supply water to cool the 460-megawatt No. 1 reactor.Although a backup cooling system is being used, Japan's nuclearsafety agency said pressure inside the reactor had risen to 1.5times the level considered normal.
Authorities said radiation levels had jumped 1,000 times normalinside Unit 1 and were measured at eight times normal outside theplant. They expanded an earlier evacuation zone more thanthreefold, from 3 kilometers to 10 kilometers (2 miles to 6.2miles). About 3,000 people were urged to leave their homes in thefirst announcement.
Tokyo Electric Power Co. warned of power shortages and an"extremely challenging situation in power supply for a while."
The utility, which also operates reactors at the nearbyFukushima Daini plant, later confirmed that cooling ability hadbeen lost at three of four reactors there, as well as a secondFukushima Daiichi unit. The government promptly declared a state ofemergency there as well. Nearly 14,000 people living near the twopower plants were ordered to evacuate.
The level outside the 40-year-old plant in Onahama, a city about170 miles (270 kilometers) northeast of Tokyo, is still consideredvery low compared to the annual exposure limit, said Ryohei Shiomi,an official with the Japan Nuclear and Industrial Safety Agency. Itwould take 70 days of standing at the gate to reach the limit, hesaid.
The Defense Ministry said it had sent troops trained to dealwith chemical disasters to the plants in case of a radiationleak.
A large fire erupted at the Cosmo oil refinery in the city ofIchihara and burned out of control with 100-foot (30-meter) flameswhipping into the sky.
Most trains in Tokyo started running again Saturday after thecity was brought to a near standstill Friday. Tens of thousands ofpeople were stranded with the rail network down, and the streetswere jammed with cars, buses and trucks trying to get out of thecity.
The city set up 33 shelters in city hall, on university campusesand in government offices, but many planned to spend the night at24-hour cafes, hotels and offices.
The quake struck at a depth of six miles (10 kilometers), about80 miles (125 kilometers) off Japan's east coast, the USGS said.The area is 240 miles (380 kilometers) northeast of Tokyo. Severalquakes hit the same region in recent days, including one measuredat magnitude 7.3 on Wednesday that caused no damage.
"The energy radiated by this quake is nearly equal to onemonth's worth of energy consumption" in the United States, USGSscientist Brian Atwater told The Associated Press.
Japan's worst previous quake was a magnitude 8.3 in Kanto thatkilled 143,000 people in 1923, according to the USGS. A magnitude7.2 quake in Kobe killed 6,400 people in 1995.
Japan lies on the "Ring of Fire" - an arc of earthquake andvolcanic zones stretching around the Pacific where about 90 percentof the world's quakes occur, including the one that triggered theDec. 26, 2004, Indian Ocean tsunami that killed an estimated230,000 people in 12 countries. A magnitude-8.8 temblor that shookcentral Chile in February 2010 also generated a tsunami and killed524 people.
Associated Press writers contributing to this report: JayAlabaster, Mari Yamaguchi, Tomoko A. Hosaka and Yuri Kageyama inTokyo; Jeff Donn in Boston; Seth Borenstein and Julie Pace inWashington; Ryan Nakashima in Los Angeles; Alicia Chang inPasadena, Calif.; and Mark Niesse in Ewa Beach, Hawaii.