Sept. 26 (Bloomberg) -- An earthquake of magnitude 8 shook Japan's northern island of Hokkaido just before dawn, injuring 472 people and causing power outages, flight cancellations and a fire at an oil refinery.

The Japan meteorological office issued a tsunami warning for the Pacific coastal areas of Hokkaido and northern Honshu. Waves of about 1.3 meters (4 feet) struck the coast after the tremor. Repeated tsunamis are still possible as of 4:30 p.m. Japan time, the agency said on its website. U.S. officials warned tsunamis could strike Russia or as far away as Guam.

The quake, the largest recorded in the world this year, was centered about 65 miles (105 kilometers) off the coast of Hokkaido, according to measurements by the U.S. National Earthquake Information Center in Golden, Colorado. The town nearest to the quake's epicenter is Kushiro, on Hokkaido.

Japan Airlines System Corp. and All Nippon Airways Co., the country's two biggest carriers, canceled flights to and from Kushiro, after air traffic control was disrupted by the quake.

Japan Airlines's Japan Air System Co. unit canceled 12 flights and another unit, Hokkaido Air System Co., canceled 14 flights, spokesman Hirohide Ishikawa said. All Nippon Airways canceled two flights between Tokyo's Haneda airport and Kushiro, said spokesman Kunio Shibata.

Hokkaido Railway Co. suspended all train services for safety checks after the quake, spokesman Keita Yamaguchi said. While some lines are already back to normal, the island's Kushiro and Obihiro lines are still suspended, he said.

Meanwhile, ``shinkansen'' high-speed trains operated by East Japan Railway Co. in northern Japan are running normally, said spokesman Hideki Fukaya.

Second Quake

Hokkaido, one of Japan's four main islands, is about the size of Austria and has a population of 5.7 million.

The quake took place at about 4:50 a.m., Waverly Person, a geophysicist at the U.S. quake center said. The epicenter was located about 490 miles (788 kilometers) north-northeast of Tokyo, he said.

A total of 472 people had been injured in the Kushiro, Obihiro and other areas in Hokkaido as of 6 p.m., according to NHK news. Hokkaido experienced earthquakes of similar magnitudes in 1993 and 1994.

About 9,100 homes in Kushiro were without power for several hours and more than 100 people had been admitted to local hospitals as of 1 p.m., said Yasuharu Nakai, assistant director at Kushiro City's general affairs division. ``The (quake's) horizontal oscillation was very strong,'' Nakai said.

A second quake, with a preliminary magnitude of 6, was recorded in southern Hokkaido just over an hour after the first quake, Kyodo News reported. Aftershocks of magnitude 3.3 and 3.7 were detected in Alaska, the U.S. earthquake center said.

Refinery Fire

Idemitsu Kosan Co., Japan's second biggest oil refiner, said it shut a 140,000-barrel-a-day refinery in Hokkaido because of a fire caused by the earthquake.

The quake also triggered an automatic shutdown of Hokkaido Electric Co.'s Tomato-Atsuma power station, causing a blackout affecting more than 160,000 customers, spokesman for the Sapporo- based company Yoshihiro Akiyama told Bloomberg News. Japan's military is preparing to provide water in areas where supplies were cut off, NHK said.

Last Updated: September 26, 2003 05:23 EDT