No buildings had collapsed, but that there had been strong shaking and people fled outdoors

An earthquake measuring 6.5 in magnitude struck China's remote and mountainous southwestern province of Sichuan on Tuesday, the U.S. Geological Survey said.

The quake struck in a sparsely populated area 200 km (120 miles) west-northwest of the city of Guangyuan at a depth of 10 km (6 miles), the USGS said. It had earlier put the quake at magnitude 6.6 and 32 km deep.

The Sichuan earthquake administration said the epicentre of the tremor was in Ngawa prefecture, largely populated by ethnic Tibetans, many of whom are nomadic herders, but also close to the Jiuzhaigou nature reserve, a popular tourist destination.

The area is frequently struck by earthquakes. Pictures on state media-run social media sites showed some minor damage in Jiuzhaigou, with tiles having fallen from buildings and people gathering outdoors, but no major damage.

State television cited a resident in a village near Jiuzhaigou as saying no buildings had collapsed, but that there had been strong shaking and people had fled outdoors.

Shaking was felt in the provincial capital Chengdu and as far away as Xian, home of the Terracotta Warriors, according to users of Chinese social media.

A quake in Sichuan in May 2008 killed almost 70,000 people.