If a 7.6-magnitude earthquake shook western Japan, almost 42,000 people could die. It's more than six times the number of victims from 1995 quake in the region, task force officials reported.
The January 1995 quake that struck the western port city of Kobe had a magnitude of 7.2. It killed 6,400 people and destroyed tens of thousands of buildings.
The Central Disaster Prevention Council said on its Web site that about 42,000 could be killed if a magnitude 7.6 inland quake hit western Japan, which includes the cities Osaka and Kobe, at 5 a.m. in the winter.
Japan is one of the world's most earthquake-prone nations. Officials say Tokyo has a 90 percent chance of being hit by a major quake in the next 50 years.
The government has estimated that 11,000 people would die and Japan would suffer about 112 trillion yen (US$950 billion; Ђ790 billion) in economic damage if a major earthquake were to strike Tokyo, home to about 35 million people, or a quarter of the country's population.