At least 12 people have been confirmed dead and rescue efforts are under way after a magnitude 6.0 earthquake struck near Yibin city in southwestern China.
The earthquake struck Sichuan province late on Monday night and was followed by aftershocks into Tuesday morning, one of which registered at 5.1-magnitude.
The city's press office said more than 70 houses had collapsed and that at least 134 people were injured. Rescue officials said hundreds of firefighters had been deployed in the area and eight people had been pulled free from destroyed homes.
And the state broadcaster CCTV reported that a hospital in Changning county had transferred all of its patients because of building damage.
Cracks appeared in several streets, according to the state's Xinhua news agency, while a major road connecting Yibin and neighbouring Xuyong County was closed.
Officials said more than 4,000 people were being moved to safety due to damage to buildings.
Xinhua reported that an early warning system activated in the state capital, Chengdu, about one minute before the earthquake. A siren rang out in Yibin around 10 seconds before the quake hit, the news agency reported.
Chengdu's early warning system was installed last year. At the time, Chinese scientists said an advance warning of three seconds could prevent up to 14 per cent of earthquake casualties, while 10 seconds' warning could prevent 39 per cent.