A series of earthquakes has hit south-west China, leaving at least 64 people dead and 715 injured, state-run media say.
The quakes struck the border of Yunnan and Guizhou provinces, with the largest felt at 11:19 Beijing time (03:19 GMT), Xinhua news agency said.
The US Geological Survey registered the two strongest of the series of quakes at 5.6 magnitude.
The quakes affected mostly mountainous areas that saw landslides, reports say.
Premier Wen Jiabao is making his way to the area, according to Xinhua.
Zhang Junwei, a spokesman from the Yunnan seismological bureau, told the Associated Press (AP) agency that most of the deaths were from Yunnan's Yiliang county.
"The casualty number is still being compiled. I don't know what was like for the other towns, but my town got hit badly," another government official in Yiliang told AP.
No deaths have been reported in Guizhou so far.
Aid agencies say they are concerned about the plight of children in the two provinces following the quakes.
"We are especially worried about those who may have been separated from their parents, as more aftershocks are expected to hit the area," Save the Children in China Country Director Pia MacRae said.
The death toll may rise further, especially in areas affected by landslides, Xinhua says.
"Roads are blocked and rescuers have to climb the mountains to reach hard-hit villages," Li Fuchun, head of Yunnan's Luozehe town, was quoted as saying.
Xinhua reported that at least 100,000 people have been evacuated and earlier reports said that more than 20,000 houses were damaged.
Mobile and regular phone service in the area was experiencing disruption, according to reports.
Hundreds of local residents had gathered on streets littered with bricks and rocks, television footage from state-run broadcaster CCTV showed.
Users of the Twitter-like wesbite Weibo reported people rushing out of shaking office buildings, and photos posted online also showed streets strewn with rubble.
Hotel staff in the city of Zhaotong in Yunnan told the BBC that the quake shook the building, knocking things from tables and shelves, reports the BBC's John Sudworth.
They said that people had been asked to leave their rooms and traffic had stopped in the streets, but there are no signs of panic, our correspondent adds.
Local officials said teams had been sent to distribute tents and blankets to those affected.
The largest of the quakes was also felt in the neighbouring province of Sichuan, where a 7.8 magnitude quake in 2008 left tens of thousands dead.