A magnitude 6.3 earthquake hit the northern Japanese island of Hokkaido (search) on Tuesday, shaking computers and desks in offices but causing no injuries or substantial damage.

There was no danger of tsunami (search), or waves caused by seismic activity, from the quake, the nation's Meteorological Agency said.

The quake, which struck shortly after 11 p.m., was centered 550 miles northwest of Tokyo.

NHK television footage showed computers and books shaking on office desks in its Kushiro broadcast center.

Yasuhiko Sada, a manager at the town hall in Akkeshi, where the earthquake shook most violently, told NHK the lights were on in the city and he had not seen any damage. A magnitude 6 quake can cause severe damage.

He added there had been no reports of any injuries.

The earthquake hit on the first day of the World Conference on Disaster Reduction (search) being held in the western Japanese city of Kobe.

Delegates aim to help lay the foundation for a tsunami early warning system for the Indian Ocean to protect people from disasters like the Dec. 26 Indian Ocean tsunami that slammed into 11 countries across Asia and Africa, killing more than 160,000 people.

The U.N. sponsored conference was timed to coincide with the 10th anniversary of the magnitude 7.3 earthquake that struck Kobe on Jan. 17, 1995, killing more than 6,400 people.

Japan, which rests atop several tectonic plates, is among the world's most earthquake-prone countries.

The country suffered its deadliest quake since Kobe in October when a magnitude 6.8 temblor rocked the northern Japanese region of Niigata, killing 40 people and injuring more than 2,700.