Millions of people in Europe, the Middle East and Asia are at risk from deadly tremors that can strike out of the blue in unmapped earthquake zones, scientists have warned.
Attention should be focused on these regions, which lie within the interior of continents, instead of well known earthquake "hotspots", according to two leading experts.
They stress that "interior zone" earthquakes kill far more people than those in recognised danger areas on continental edges such as in Japan and California.
Over the past century, earthquakes on large fault lines where shifting plates of earth's crust collide and slip have claimed around 800,000 lives, say the experts writing in the journal 'Nature Geoscience'.
Around half these deaths were due to tsunamis, like the one that struck the north-east coast of Japan in March.
In contrast, sudden earthquakes in continental interiors within the plates have killed around 1.4 million people. Interior quakes also killed far more people directly by shaking the ground and toppling buildings.
Professor Philip England from Oxford University and Professor James Jackson from Cambridge University classified 130 earthquakes occurring in the last 120 years.
The experts argued that more scientific resources should be directed at identifying seismic risk in regions such as the 10 million square kilometre Alpine-Himalayan belt, which covers Italy, Greece, Turkey, Iran, central Asia and China.
The scientists wrote: "On the plate boundaries, the location of the hazard is well known and earthquake timing constitutes the greatest uncertainty.
"In many parts of the continental interiors, however, we do not even know where the hazards lie.
"We argue that the knowledge that underpins earthquake resilience in Japan or California must be transferred to countries in which earthquakes regularly inflict huge death tolls, often far from the media spotlight," they added.