MIANYANG, China - China poured more troops into the earthquake-ravaged province of Sichuan on Wednesday to speed up the search for survivors as time ran out for thousands of people buried under rubble and mud.

Weary rescuers pulled at tangled chunks of buildings and peered into crevices for signs of life after Monday's 7.9 magnitude quake crumpled homes, schools and hospitals.

The government dispatched 50,000 troops to the south-western province to dig for victims as the national death toll climbed past 13,000. It is likely to rise steeply after state media said 19,000 were buried in the province's Mianyang area alone.

On the edge of Mianyang city, people roamed around a sports ground housing the homeless, holding cardboard signs with the names of relatives in hopes of information. Most were from nearby rural Beichuan county, one of the worst-hit areas.

"They have said nothing about what's going to happen to us. This is just a temporary place. I don't know when or if we'll be able to go home," said Hu Luobing, from a Beichuan village where she said everything had been destroyed.

She was leaving her daughter in the shelter of the sports ground, where some 10,000 Beichuan survivors had gathered, to look for clothes.

Others were seeking food and relief from the cold rain.

"I've had nothing to eat since last night. I've only been given some bread and a bottle of water for my child," said Bai Chenchu, one of thousands camped out at the sports ground.

Another had only the clothes on his back.

"I'm wearing everything I own," said 15-year-old Xi Dongli.

Pictures from Beichuan, a hilly area that rescuers have struggled to reach, showed near total devastation. Survivors lay alongside the dead in the open air, surrounded by buildings reduced to mangled slabs of concrete.

PREMIER'S APPEAL

Chinese Premier Wen Jiabao, who has been in Sichuan leading rescue efforts, making emotional appeals to urge on workers and visiting crying, orphaned children, was in Beichuan by midday.

"Your pain is our pain," he said on state television. He stood amid a cluster of residents, one with blood on her head and some of whom wiped away tears. "Saving people's lives in the most important task."

Beichuan county alone was in urgent need of 50,000 tents, 200,000 blankets and 300,000 coats, as well as drinking water and medicine, Xinhua said.

"Beichuan has just disappeared. There's nothing left," said Li Changqing, a salesman in Mianyang.

Ambulances streamed down the road from Beichuan, which was closed to incoming cars so survivors and the injured could get to hospitals and shelter.

The quake, the worst to hit China since 1976 when up to 300,000 died, has muffled upbeat government propaganda three months ahead of the Beijing Olympic Games.

It has also overshadowed criticism from abroad over recent unrest in Tibet, with images of the human tragedy and heroic rescue efforts spurring offers of aid and an outpouring of sympathy.

China's stock market initially weakened after the quake, partly on fears it could add to inflation that is already at a 12-year high, but the Shanghai index ended 2.7 percent higher on Wednesday as fears of the long-term impact ebbed.

Industrial production growth released on Wednesday showed China's busy factories moving down a gear, and economists said output growth could fade further in coming months, partly due to the impact of the Sichuan quake.

FOOD AND SHELTER

At the Mianyang sports ground, local volunteers were distributing rice and water. One man handing out boiled eggs was mobbed, but desperate survivors were mostly orderly.

Central authorities have ordered stricken areas to ensure food supplies and price stability, but some Chinese news reports described price rises and shortages in quake-hit areas.

The extent of destruction in many towns across the mountainous area suggested searchers would find many more bodies than survivors among the toppled buildings.

Rain has frustrated rescuers' efforts to get to some areas and more rain is forecast for coming days.

"Everything became very difficult last night with the rain. There are a lot of people with no place to go," said Kate Janis, a programme director with the aid organisation Mercy Corps.

State media reported devastation in villages near the epicentre in Wenchuan, a remote county cut off by landslides about 100 km (60 miles) northwest of Chengdu. About 60,000 people were unaccounted for across Wenchuan, authorities said.

In Wenchuan's Yingxiu town, only 2,300 of its 10,000 residents were accounted for, Xinhua reported.

Amid the overwhelming grief, there were also moments of relief. In Sichuan's Mianzhu, about 500 people were pulled out alive from crushed buildings.

And a group of 31 British tourists visiting a panda reserve in the stricken area were safe, China's Foreign Ministry said.