China on Thursday fanned out army, civil defence forces and equipment into a mountainous Tibetan region to speed up the rescue efforts as a devastating quake of 7.1-magnitude left a trail of destruction with over 600 deaths and more than 10,000 injuries.
The death toll has risen to 617, Xinhua reported.
The trembler measuring 7.1-magnitude on Richter scale had hit the province in the Qinghai Tibetan plateau yesterday almost flattening Jiegu township, where more than 85 per cent of the houses collapsed.
Thousands of people had to spend a night without shelter in freezing temperatures.
Officials said that over 1,000 people buried under the debris have been rescued by the army, police and civil defence forces.
Near Jiegu Township, the epicentre of the tremor, many others are still buried under the debris of collapsed houses.
Chinese vice-premier Hui Liangyu, who has reached the affected areas, asked the officials last night to take rescue work as the first priority and called for joint efforts of the military forces and the local people to search and rescue the trapped in a bid to minimise the casualty, Xinhua reported.
Meanwhile, an earthquake measuring 4.0 on the Richter scale hit Atux City in northwest China's Xinjiang Uygur Autonomous Region early today, said the China Earthquake Networks Centre.
The epicentre of today's tremor was 40.1 degrees north latitude and 76.5 degrees east longitude with a depth of 9 km.
The Public Security Ministry (MPS) has dispatched 1,775 firemen, 460 police officers and 160 medical care workers from provinces and regions, including Guangdong, Sichuan, Gansu, Yunnan, Tibet and Ningxia, to the affected areas with life-detection equipment.
China's People's Liberation Army (PLA) Air Force has deployed three large planes to transport rescuers and relief materials to Yushu.
Two Il-76 aircraft have reached Yushu airport with rescuers and equipment from the national earthquake rescue team in Beijing in one, while the other has delivered 100 rescuers from China's mine exploration team, stationed in Chengdu.
The Air Force said another Il-76 heavy carrier which brings 100 geological experts and heavy vehicles will take off from Chengdu for Yushu.