By John Ruwitch
BEICHUAN, China (Reuters) - An aftershock brought new havocto the earthquake-stricken region of China on Friday, as itstruggled to bury some of its estimated 50,000 dead, dig outmore survivors and help thousands of injured and homeless.
President Hu Jintao flew to the battered province ofSichuan and Premier Wen Jiabao said the quake damage couldexceed that of the devastating 1976 tremor in the northeasterncity of Tangshan, which killed up to 300,000 people.
Wen called on officials to ensure social stability asfrustration and exhaustion grew among survivors, many of whomhave lost everything and are living in tents or in the open.
China put the known death toll at just over 22,000 onFriday but has said it expects it to eventually exceed 50,000.About 4.8 million people have lost their homes.
Thousands of men, women and children were heading on footfor Mianyang, a city near the epicentre, saying they wereabandoning their ruined villages for good.
Anger has focused on the state of school buildings, many ofwhich crumpled in Monday's 7.9 magnitude quake, buryingthousands of children and prompting the Housing Ministry toorder an investigation.
Hu and Wen stressed that searching for survivors remainedthe top priority.
"We cannot talk about giving up too easily," Wen said."Life should go on. I believe people in the quake area candefinitely build their hometowns even better with their ownhands. That is also the biggest consolation for the dead."
The country is on precautionary alert against possibleradiation leaks, according to a government Web site.
The disaster area is home to China's chief nuclear weaponsresearch lab in Mianyang, as well as several secretive atomicsites, but no nuclear power stations.
Thousands of residents from Beichuan, one of the placesworst hit, streamed away from the town carrying babies, bagsand suitcases.
The town was a scene of devastation, with virtually everybuilding either demolished or damaged beyond habitation.
To the south, in the village of Houzhuang, residents saidthey were coping on their own, aid and troops yet to reachthem.
"We ate some corn, but now we are suffering from diarrhoeaafter drinking water from the ditch for two days," one said.
BUCKLED ROADS, LANDSLIDES
The aftershock, measuring 5.9 on the Richter scale, hitLixian, to the west of the epicentre in Wenchuan, cutting newlyrepaired roads and telecommunications.
"A number of vehicles were buried in landslides. Thecasualties were not known," Xinhua news agency said, addingfour of its reporters narrowly escaped death when a housecollapsed.
China has mobilised 130,000 troops to the disaster area,but with buckled and blocked roads, supplies and rescuers havestruggled to reach the worst-hit areas.
Offers of help have also flooded in. The first foreignrescue teams, from Japan, Russia, Taiwan, South Korea andSingapore have arrived in Sichuan province.
At China's request, the World Food Programme said it wassending enough ready-to-eat meals for 118,000 people.
UN Secretary-General Ban Ki-moon announced emergency fundsof up to seven million dollars and said more would beavailable.
The United States said it had provided China with satelliteimages of earthquake-stricken areas, and would send twoplaneloads of relief for victims this weekend.
Xinhua said 33 people were dug out of the rubble inBeichuan still alive on Friday.
Peng Zhijun, 46, had eaten cigarettes and paper napkins andhad drunk his urine to survive. A 50-year-old worker wasrescued from a collapsed fertiliser plant after being trappedfor 100 hours, a witness told Reuters.
Many survivors were on the move, desperately seeking food,shelter or medical treatment. Ning Feng told Reuters he hadspent two hungry days limping out of the town of Yingxiu afterdeciding that waiting to be rescued could be more dangerousthan risking landslides and exhaustion on the trek out.
"I had to do it on my own. Who was there to help me?" the19-year-old painter of traditional Tibetan art said, as hestopped to rest on the winding mountain path.
ANGER OVER SCHOOL DEATHS
In Dujiangyan, a school collapse buried 900 students. InWufu, nearly every building in the village withstood the quakebut for a primary school, whose collapse killed about 300.
"Our child wasn't killed by the earthquake. She and theothers were killed by a derelict building. The officials knewit was unsafe," said Bi Kaiwei, whose daughter, 13, was killed.
Rescuers found two girls, one in a coma and the other dead,holding hands in the ruins of their school, Xinhua said.
Housing Minister Jiang Weixin said the schools had not beendesigned to withstand such a powerful earthquake, but addedthat corruption may have led to substandard construction.
"At this stage we cannot rule out the possibility thatthere has been shoddy work and inferior materials," Jiang tolda news conference in Beijing.
There were also concerns about epidemics if the dead werenot soon buried or cremated.
"A lot of tourists have been killed. We don't know how todeal with the bodies, some of which have been highlydecomposed, but their relatives will come to look for them," anarmy officer in the badly hit Yinmugou resort in Pengzhou toldSichuan TV.
"I am really worried about epidemics," he said.
Hundreds of damaged dams have also raised fears of collapseand flooding of areas struggling to recover from the quake.
(Additional reporting by Emma Graham-Harrison in Yingxiu,Jason Li in Houzhuang, Lucy Hornby, Benjamin Kang Lim and GuoShipeng in Beijing and Stephanie Nebehay in Geneva; editing byAndrew Roche)
