Beijing - At least 19 people were killed when two shallow earthquakes struck northwest China early Monday, a local government official told AFP as rescuers battled to reach survivors.
The US Geological Survey said the initial 5.9 magnitude quake hit at 07:45 (23:45 GMT Sunday), with its epicentre 151km west of Beidao in Gansu province at a depth of just 9.8km.
A second 5.6 magnitude tremor hit the same region at 09:12 and was 10.1km deep, USGS said.
The official, surnamed He, from the Communist Party committee in Minxian, said 19 people were dead and more than 200 injured in seven townships severely hit by the quakes.
A report on the 163.com internet news portal said 500 troops including 120 specialised rescuers were on their way to the scene.
Pictures broadcast on state television showed rural villages with rubble-strewn streets.
Much of western China is prone to earthquakes.
Beijing's own China Earthquake Networks Centre put the magnitude of the larger quake at 6.6, the official Xinhua news agency reported.
It reported that locals in Minxian county said they saw trees and homes shaking, with the quake lasting for about one minute.
It was felt in the provincial capital Lanzhou and as far away as Xian, the capital of the neighbouring province of Shaanxi.
The USGS rated it at seven on its "shakemap", with shaking perceived to be "very strong" and the potential to cause "moderate" damage.