Experts say tremor wasn't predictable

Some scientists have been puzzled by the lack precursors to the 8.0-magnitude earthquake that devastated southwest China on May 12. However, other experts believed there had been signs a major seismic event was about to take place.

"There were no foreshocks, and there weren't many minor quakes around the epicenter for quite some time before the earthquake," deputy director of the China Seismological Bureau (CSB) Xiu Jigang said.

He said there were none of the other typical precursors usually used to predict major quakes before the recent disaster, such as anomalies in wildlife behavior and groundwater levels.