A 6.3-magnitude earthquake jolted Tibet in southwestern China late Monday.

There were no immediate reports of damage or casualties.

The quake epicentre was 225 kilometres (140 miles) northeast of Jumla, Nepal, and struck at a depth of 35 kilometres, the US Geological Survey said.

No casualties have been reported, according to the official Xinhua news agency, which said the quake measured 6.8 on the Richter scale.

The area in southern Tibet, located at an average altitude of 5,500 metres, is sparsely populated, Xinhua said.

Two aftershocks, of 5.3 and 5.2 magnitudes, later rattled the area, the USGS said.

A massive quake hit southwest China's Sichuan province in May, leaving nearly 70,000 dead, with about 18,000 people still missing.

© 2008 All rights reserved. Citing to ANS PRESS is necessary upon using news.