7.2 Quake Hits Western Japan; At Least 197 Die : Disaster: Hundreds are hurt in Kobe region, many trapped in collapsed buildings. Trains derailed, freeways buckled by nation’s strongest urban temblor in decades.

A powerful earthquake rocked western Japan before dawn today, killing at least 197 people and trapping as many as 400 more as buildings collapsed, trains derailed, elevated railways and expressways buckled and fires erupted in the major port city of Kobe.

The quake, which shook buildings as far away as Kyoto about 40 miles away, was measured at magnitude 7.2 at its epicenter, at Awaji Island about 20 miles from Kobe, a city of 1.5 million 270 miles west of Tokyo.

It struck at 5:46 a.m.--an eerie coincidence for Southern Californians marking the first anniversary today of the 6.7 Northridge quake, which also occurred near daybreak.

As reports of extensive damage continued to pour in, fires were still burning in at least seven sections of Kobe more than four hours after the earthquake struck. Most of the fatalities were reported in and around Kobe.

Police in the neighboring city of Ashiya reported that 69 buildings there had collapsed.

Television showed dozens of families taking refuge from their ruined homes on mattresses spread out on streets and sidewalks. Entire blocks of buildings were reduced to rubble. Apartment buildings and hotels tilted.

The first floor of a hotel in Kobe collapsed, and TV cameras showed guests being helped out of second-floor windows. Glass shattered in windows throughout the area.

On one expressway where part of the elevated pavement had fallen to the ground, TV cameras showed a bus dangling perilously from the broken end of the highway. There was no sign of passengers inside the bus.

A truck was shown sandwiched between two collapsed sections of an expressway, but it was unclear whether it was the same freeway.

Trains were reported derailed at seven locations. No information was available on injuries in the derailings.

Helicopter TV cameras showed at least three commuter railway cars overturned at one station. Fires were sweeping through shops adjacent to the station.

Rail travel was halted throughout the area, and authorities closed all expressways. NHK television footage showed twisted expressways, collapsed sections of highway, and an entire elevated railway yard that had folded down to the ground in the middle.

NHK showed film of its Kobe office being shaken violently by the tremor, which toppled filing cabinets and moved desks several feet.

A housewife in Kobe told NHK that she woke up as the earthquake hit.

“The door of the refrigerator was open and food from inside was spilled over the floor of the kitchen,” she said. “Soup that I left in a pot on the stove was splashed all over the floor and a bottle of sake was broken. Everything was in a mess.”

A resident of Nishinomiya, a town near Kobe, told Reuters news agency she was shaken awake in her third-floor apartment. “There was a big shaking, I felt like I was being thrown into a deep pit like hell. It was so big. It was a terrible shaking,” she said.

Telephones were reported operating, although lines reserved for emergency calls to police and the fire department were swamped with calls, making communications difficult or impossible.

Itami Airport in nearby Osaka continued to operate, but flights were reported delayed at the new multibillion-dollar Kansai Airport on an artificial island in Osaka Bay off Kobe. Trains on the Bullet Line from Tokyo were reported being halted at Nagoya.

Today’s earthquake, NHK said, was the biggest to strike an urban area since a 6.1-magnitude quake severely damaged the city of Fukui in 1948. And it was the fifth major temblor in the magnitude 7 range to shake parts of Japan since Oct. 4. But unlike the others, which were out to sea off northern Japan, this one was centered very close to a highly urbanized area.

That proximity to populated areas, plus the quake’s comparatively shallow depth of 12 miles as estimated in first reports, caused damage and casualties that quickly exceeded those of earlier quakes.

As in the weaker Northridge quake, the Japanese temblor could be a major demonstration of how steel frame and other high-rise buildings fare under heavy shaking, U.S. scientists said.

Hiroo Kanamori, director of the Caltech Seismological Laboratory, who was born and educated partly in Japan, told colleagues in Pasadena that the area west of Osaka and near Kobe where today’s quake struck had not suffered many quakes in the past.

While Japanese authorities put the preliminary magnitude at 7.2, several times stronger than the Northridge quake, U.S. scientists at the National Earthquake Information Center in Golden, Colo., said their preliminary assessment assigned it a magnitude of 6.9, about twice as powerful. It is common for preliminary estimates to differ.

Kanamori said in an interview that today’s quake occurred 130 miles from one tectonic plate boundary, known as the Nankai Trough, and 30 miles from a second plate boundary, in an area that had not been the focus of any Japanese earthquake prediction experiments.

“This is not really a large event by Japanese standards,” he said, “but since it is near a highly populated area, like Northridge, it’s done quite a bit of damage.”

Japanese scientists have long expressed concern about a major quake on the Nankai Trough, just as California scientists have long pointed to the San Andreas fault as the eventual site of great quakes.

But, as in both the Northridge quake and the 1971 Sylmar quake, the first sizable temblor to strike in the vicinity came at an unexpected location, well away from the famous geological faults.

Only nine days ago, three major tremors struck Japan. They ranged in magnitude from 5.2 just outside Tokyo to 6.9 and 4.2 in Hachinohe, 325 miles north of the capital.

Earthquakes with a magnitude of more than 7 struck rural areas of northern Japan three times in 1993.

Times staff writer Kenneth Reich in Los Angeles contributed to this report.