More than 250 people have died after an earthquake hit China's north-western region of Xinjiang on Monday morning.
The death toll is expected to rise as news comes in from outlying areas of the arid region.
"If you ask me how many people
have been injured, I can only use the word 'countless' at the
moment," local official Han Chubai told Reuters news agency.
The quake struck 40 kilometres (24 miles) east of Jiashi city, near the border with Kyrgyzstan and Tajikistan, toppling homes and schools.
The official Xinhua news agency said it had a magnitude of 6.8, while the US Geological Survey said it measured 6.3.
Subsequent aftershocks have forced many people to remain outdoors in freezing temperatures.
Officials in the provincial capital Urumqi are organising shipments of relief supplies, while relatives of the victims in the predominantly Muslim region are preparing for funerals.
Lots of buildings here collapsed. There is no electricity. Lots of people are outside now and no one dares stay at home
Businessman Zhou Mingcheng said he and his family just managed to escape from their collapsing home in Arlagen village in Bachu county.
"We were sleeping at the time, and it was still dark. We
ran out immediately when it began to shake."
More than 100 people in his village
of 1,000 were feared dead, he said.
"Lots of buildings here collapsed. There is no electricity.
Lots of people are outside now and no one dares stay at home."
A doctor at the People's Hospital in Bachu
said all the beds were full.
"The injured are being admitted to the hospital one after
another. We are still counting the numbers," he said.
'Poor quality buildings'
Xinjiang Seismology Bureau official Li Qianghua blamed the high death toll on the poor quality of buildings in the area.
The tremor was felt in the bureau's headquarters in the historic oasis city of Kashgar, about 150 km (100 miles) away from the epicentre.
The quake was also felt in Urumqi, more than 1,000 km (600 miles) to the north-east.
US Secretary of State Colin Powell, in China for talks on Iraq
and North Korea, said: "I was sorry to learn... of the
earthquake in western China and the loss of life.
"I want to express my regrets to the Chinese people."
History of quakes
Jiashi county, an area populated mostly by members of the Muslim Uighur minority, has suffered a number of powerful earthquakes in the past few years.
But the sparse population has meant that casualties have usually been low.
More than 20 people were killed in March 1996 when a
quake of 6.9 magnitude hit an area 120
km (75 miles) north of Jiashi.
A further 12 people were killed in a quake in January 1997, and another nine died in a subsequent tremor in April of the same year.
Earthquakes in more populated regions have had a much higher death toll.
A quake measuring 7.9 shook Tangshan
near China's capital Beijing in 1976, killing an estimated 250,000 people.
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