TOKYO (Reuters) – A major earthquake with a magnitude of 7.2 jolted northern Japan on Tuesday, injuring at least 59 people, causing power outages and bringing trains to a halt, stranding thousands of passengers.

Buildings also swayed in Tokyo, about 300 km (190 miles) to the south, when the tremor struck at 11:46 a.m. (0246 GMT) but there were no reports of damage or injuries in the capital.

Public broadcaster NHK said at least 22 of the 59 injured were hurt when the ceiling at an indoor swimming pool collapsed in Sendai, an industrial city of about one million.

&#34There was a tremendous boom … People were screaming and headed toward the exit. It shook a lot … A lot of people were crying,&#34 a young woman who was at the pool told NHK.

Television showed the injured in swimsuits outside the pool and rescue workers sifting through wreckage in the water.

Several aftershocks followed the initial quake, the largest with a magnitude of 4.5, the Japan Meteorological Agency said.

Trains were halted including high-speed &#34bullet&#34 train services, leaving 3,200 passengers stranded between stations more than five hours after the quake, NHK said. Other passengers walked along the rails to the nearest station.

About 200 houses were damaged, mostly in northern Japan, Kyodo news agency said.

A tsunami measuring about 10 cm (4 inches) high hit the coast of Miyagi prefecture, but a tsunami warning was lifted about 90 minutes after the initial quake.

Tokyo”s major airports resumed operations after runways were briefly closed for checks. One highway was also briefly closed.

A woman was rescued after being trapped when her wooden house collapsed in Saitama, west of Tokyo, media reports said.

At one point nearly 17,000 households were without electricity but power supplies were gradually recovering, said Tohoku Electric, the main supplier to the affected region, which has several high tech factories.

The focus of the tremor was 42 km (26 miles) below the seabed off the coast of Miyagi, the Meteorological Agency said.

Tohoku Electric said all three nuclear power generators at its Onagawa plant in the region stopped automatically after the quake and Nippon Oil suspended operations at its local refinery.

Sony Corp (NYSE:SNE – news)., which has factories in Miyagi making magnetic tapes and semiconductor lasers, said there was no impact from the quake on its facilities and no staff were injured.

Fuji Photo Film Co. said production at its digital camera factory in Miyagi was temporarily halted for checks but it reported no damage to equipment.

The magnitude of the quake was measured according to a technique similar to the Richter scale, but adjusted for Japan”s geological characteristics.

The coastal area off Miyagi prefecture has suffered powerful quakes in the past due to friction between the Continental and Pacific plates. In 1978, a tremor originating in the same area killed 28 people and injured more than 10,000, Kyodo news agency said.

Earthquakes are common in Japan, one of the world”s most seismically active areas. The country accounts for about 20 percent of the world”s earthquakes of magnitude 6 or greater.

In an average year there are less than 20 earthquakes in the world with magnitudes of seven and above.

In October 2004, an earthquake with a magnitude of 6.8 struck the Niigata region in northern Japan, killing 40 people and injuring 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.