A huge earthquake of magnitude 6.5 has jolted central China, the US Geological Survey reports.

The USGS said the tremor struck in a sparsely populated area 200km (120 miles) west-northwest of the city of Guangyuan in Sichuan area at a profundity of 10km (6 miles), the USGS said.

It had before putting the tremor at magnitude 6.6 and 32 km profound. Shallow tremors tend to cause more harm than more profound ones. There were no quick reports of damage from the territory, which is frequently struck by seismic tremors.

Shaking was felt in the capital Chengdu and as far away as Xian, home of the Terracotta Warriors, as indicated by users of Chinese online networking.

The epicentre of the quake was in Ngawa prefecture, largely inhabited by ethnic Tibetans.

The China Earthquake Networks Center measured the tremor at magnitude 7.0 and said it was 20km (12 miles) profound.

The Chinese office said the shake happened around 9:20 pm close Jiuzhaigou, or Jiuzhai Valley, a national stop known for marvellous waterfalls and karst arrangements.

In May 2008, Sichuan quake killed almost 70,000 people.