BEIJING, Oct. 11 -- The seismic intensity of the 6.6-magnitude earthquake that jolted southwest China's Yunnan on Tuesday evening peaked at level VIII on the 12-level MMI (modified mercalli intensity) scale at its epicenter, the China Earthquake Networks Center announced on Saturday.

The quake, with a focal depth of five kilometers, centered around Jinggu county with a population of 290,000.

One person died and 324 others were injured after the quake.

A total area of 400 square kilometers were affected by the intensity of VIII, while another 11,530 square kilometers were covered by intensities above VI.

It's the second strong quake to hit the province in two months. A 6.5-magnitude quake struck the county of Ludian on Aug. 3, killing at least 615 people.

The severity of an earthquake is described by both magnitude and intensity. Magnitude, usually expressed as an Arabic numeral, characterizes the size of an earthquake by measuring the energy released.

Intensities are expressed in Roman numerals indicating the local damage produced by an earthquake on the Earth's surface as it affects humans, animals, structures and natural objects. ( Any given earthquake can be described by only one magnitude, but many intensities since the earthquake effects vary with circumstances such as distance from the epicenter and local soil conditions.

Ranging from I to XII, a Level VI on the MMI indicates that the tremor could be felt by all in the area and is capable of causing minor structural damage. At level VIII, a quake can result in considerable damage to structures.