At least 156 people were killed and more than 5,000 injured when a magnitude-6.6 earthquake struck Saturday in south-west China, destroying buildings and triggering landslides, dpa reported with a reference to state media.
Ten military aircraft carrying some 7,500 soldiers from across China were descending on a mountainous area of Sichuan province in hopes of rescuing those who might still be trapped in the rubble, the official Xinhua news agency reported.
The quake, which was initially reported as registering 6.9 or 7.0, struck Lushan county at 08:02 am (0002 GMT), according to the US Geological Survey.
Many roads in the region are reported to be impassable and telephone connections are spotty. The Civil Affairs Ministry said it is sending relief supplies to the region, including 30,000 tents and 50,000 blankets.
Four hours after it first struck, 264 aftershocks had been registered, two measuring more than 5.0.
Shaken residents, fearing the collapse of more damaged buildings and homes, had taken to sheltering in tents.
Premier Li Keqiang travelled to the city of 1.5 million residents on Saturday to witness the extent of the destruction and support recovery efforts.
"The most important thing now is to make use of the first 24 hours after the quake. It is the crucial time to save lives," Xinhua quoted Li as saying.
The government's response to a magnitude-8.0 quake that struck the same region in May 2008 was criticized as being too slow. Nearly 90,000 people were killed then.