Earthquakes are dangerous because they strike without warning.
Buildings and communities near active earth-fault zone or on soft or unstable soil or slopes or at water's edge are especially vulnerable to ground shaking. Dense urban earthquake coupled with weak building structures along the epicenters are responsible for most fatalities. In 1999 alone, more than 25,000 people were killed due to earthquakes. The deadliest year was 1976 when at least 250,000 people were killed and more than 800,000 injured after one quake rocked in China . It felt the fatal effects when a magnitude 6.3 killed 2000 people.