Strong quake jolts Tokyo

A strong earthquake jolted Japan's capital Tokyo and nearby areas yesterday, shaking buildings and injuring at least 18 people, the weather office and media reports said.

The 6.0 magnitude quake at a depth of 73 km in Chiba prefecture near Tokyo halted trains and briefly closed airports.

Japan's Meteorological Agency said, which initially gave the quake's magnitude as 5.7, said there was no risk of a tsunami.

It warned of possible aftershocks in the next few days, Kyodo news agency said.

Public broadcaster NHK said 18 people were injured in the earthquake.

"There was shaking from side to side... The escalator shook and it was scary," a young woman in Shibuya, a busy shopping district in Tokyo, told NHK.

The quake triggered panic in an indoor ice rink in Kanagawa, south of Tokyo.

"The whole building was shaking... About 70 people were on the rink and people were screaming and scrambling to get off the ice," a Reuters witness said.

Among the injured were five women who were hurt by a falling sign in a supermarket in Konosu city north of Tokyo and a 93-year-old woman who fell off her porch, NHK said.

A fire broke out at a three-storey house in Meguro ward in Tokyo and there were at least 15 reports of people being trapped inside elevators, a Tokyo Fire Department spokeswoman said.

The earthquake also caused a steel tower to collapse in Tokyo, damaging the roof of a nearby building, media said.

Earthquakes are common in Japan, one of the world's most seismically active areas. The country accounts for about 20 per cent of the world's earthquakes of magnitude 6 or greater. Many train services were halted and road were closed.

Two Tokyo-area airports shut down for checks but later resumed operations, as did some train services.

Another witness said he saw a car park swaying in eastern Tokyo and that elevators had stopped at an apartment complex.

A government disaster prevention panel that examined disaster scenarios for Tokyo said in February the capital could suffer damages of around 1 trillion yen and 13,000 deaths if an earthquake of around magnitude 7.0 hits Tokyo.

The Great Kanto Earthquake of 1923, an 8.3 magnitude tremor, killed more than 140,000 people in Tokyo and neighbouring cities.

In October 2004, an earthquake with a magnitude of 6.8 struck the Niigata region, killing about 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 that killed more than 6,400 people.