The earthquake that killed one person in southwest China's Sichuan Province Sunday was not an aftershock of the 8-magnitude quake of May 12, 2008, said Lu Yipei, deputy director of Sichuan Provincial Seismological Bureau, Monday.

Experts were still investigating the cause of the 5-magnitude quake, he said.

"We are sure this quake is not an aftershock because of change in geological structure and environment caused by the devastating quake in May 2008, which left about 87,000 people dead or missing," Lu said.

The earthquake, which struck the juncture of Sichuan's Suining City and Tongnan County of Chongqing Municipality at 5:36 AM Sunday, also injured 15 people and caused more than 2,000 to be relocated as of Sunday.

Its epicenter is located at 30.3 degrees north latitude and 105.7 degrees east longitude, with a depth of about 10 kilometers.

The possibility of aftershocks could not be ruled out, said Chen Tieliu, director of Chongqing's earthquake bureau.

(Xinhua News Agency February 1, 2010)