Tens of thousands of homeless survivors of China's devastating quake are living in makeshift tents or on the streets, facing shortages of food and supplies as well as an uncertain future.

Saturday's disaster has left at least 193 dead, 25 missing and more than 12,000 injured, and forced the evacuation of some 245,000 people in Sichuan province in China's mountainous southwest, according to Chinese and UN data.

Along Chonglu Road, which cuts through the heart of the worst-affected area in Sichuan's Lushan county, hundreds of tents have been erected in front of piles of debris that were once orderly rows of homes.

Many of the displaced headed for the relative safety of Lushan's densely populated centre, spending their nights outdoors in sleeping bags on the grassy mounds surrounding Lushan People's Hospital.

But others have not left the rubble where their destroyed homes once stood, and instead sleep in tents they have erected themselves by using sticks and canvas, or in bright blue shelters provided by relief agencies.

An elderly woman from the devastated village of Longmen sat forlornly in front of a pile of debris, and shrugged when asked where she was going to shelter that night as rain started to pour.

"Nobody has offered me anywhere else to sleep," she told AFP, pointing to her meagre dwelling -- a sheet of canvas strung from two trees and a dirty blanket that lay on the floor beneath.

"What else can I do?"

Nearby, a woman called Ye Helian said that assistance offered by the government would not be enough to support her while she remained homeless.

"I had a business sewing clothes for the community, and as I worked from home, I have no means of support," she said.

Others though said they counted themselves fortunate, as while they had lost their homes, their loved ones survived the quake and a terrifying succession of some 3,000 aftershocks.

"That's my house over there with the most damage," said 38-year old Wu Yao, pointing to a flattened two-storey property.

"My luck is fine. If it wasn't, then I wouldn't have anything."

The rescue and relief effort has been hampered by the region's forbidding landscape, with high-altitude roads blocked by boulders and landslides and emergency workers in fear of further sudden slippages.

The People's Liberation Army has used helicopters to airdrop supplies including bottled water and instant noodles to survivors in Lushan, the official Xinhua news agency reported.

But state-run media have reported severe shortages of essential goods in many of the affected counties that together with Lushan lie within Ya'an city.

China News Service said that in Tianquan county, victims are in desperate need of water, food, quilts and medicine.

And Beijing News reported that neighbouring Baoxing county was also suffering from a shortage of tents. Longmen town also lacks enough medication to treat the injured, as well as shelter materials, state media said.

Thousands of volunteers have rushed to the region from across China but have now been told to avoid the quake-stricken area, after being blamed for traffic congestion that has also disrupted rescue efforts.

"There are limits to how many volunteers we can absorb," Han Bing, the top official in Baoxing, told the state-run Global Times, adding there were more than 3,000 unofficial volunteers in the county already.

Problems facing the rescue effort have been "made worse by the number of 'disaster gawkers' who like to refer to themselves as 'volunteers' despite the fact that they'll often do more harm than good", said the Economic Observer.

One volunteer who travelled to the area was a soldier surnamed Li, who journeyed from Chengdu city several hours' drive away.

"I had to come to help, but I haven't been able to get near the area as the roads are blocked," he said. "There are probably too many people volunteering."

Chinese media have given blanket coverage to the aftermath of the 6.6 magnitude tremor, which struck close to the epicentre of an enormous 2008 quake that left 90,000 dead or missing.

Donations have poured in from ordinary citizens, while many have expressed support for victims in Twitter-like microblogs.

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