LHASA, July 10 (Xinhua) -- An earthquake measuring 4.6 on the Richter scale struck Ngamring County, Xigaze in southwest China's Tibet Autonomous Region Saturday evening. No casualties have been reported yet.

The earthquake, whose epicenter was traced at 20 kilometers northwest to the town proper of Ngamring County, occurred at 6:15 p.m., said the earthquake monitoring network in Tibet.

Cracks were found on some of the local houses but no deaths or injuries were reported, local officials told Xinhua.

Ngamring County, with a population of 40,000, covers 28,000 square kilometers of land on the Qinghai-Tibet Plateau with an average elevation of 4,300 meters above the sea level.

A 7.1-magnitude quake struck Yushu, Qinghai Province neighboring Tibet, on April 14, killing more than 2,200 people and flattening thousands of homes.