HANWANG, China - Thousands of Chinese soldiers rushed Wednesday to repair a dam badly cracked by the country's massive earthquake, while rescuers arrived for the first time in the epicentre of the disaster to find whole villages flattened.

The death toll in Monday's massive quake stood at almost 15,000, but with tens of thousands of people still missing and buried, there were fears it could soar much higher.

China's top economic planning body said the quake damaged 391 mostly small dams.

Bit also left "extremely dangerous" cracks in the Zipingpu Dam upriver from the earthquake-hit city of Dujiangyan and some 2,000 soldiers were sent to repair the damage, the official Xinhua news agency reported.

Xinhua said Dujiangyan would be "swamped" if major problems emerged at the dam.

He Biao, director of the Aba Disaster Relief headquarters in northern Sichuan province, said there were also concerns over dams closer to the epicentre.

"Currently, the most dangerous problems are several reservoirs near Wenchuan," he said, according to a transcript on the China Central TV website.

"There are already serious problems with the Tulong Reservoir on the Min River. It may collapse. If that happens, it would affect several power plants below and be extremely dangerous," he said.

Rescuers who hiked in to the epicentre scoured flattened mountain villages for thousands of missing and buried victims.

Help also began to arrive helicopter in some of the hardest-to-reach areas, where some victims trapped for more than two days under collapsed buildings were still being pulled out alive.

But the enormous scale of the devastation meant that resources were stretched thin, and makeshift aid stations and refugee centres were springing up over the disaster area the size of Belgium.

Hospitals were levelled, forcing doctors and nurses to treat survivors in the street, while mourners burned money before rows of bodies, believing their lost relatives will use it in the afterlife.

Helicopters buzzed overhead, dropping food and medicine to isolated towns - part of the mobilization of 100,000 troops and police for the relief effort.

Xinhua quoted government officials as saying rescuers who hiked Wednesday into the city of Yingxiu in Wenchuan county - the epicentre of the quake - found it "much worse than expected."

Of the town's population of about 10,000, only 2,300 survived, and 1,000 of them were badly hurt.

The official death toll rose Wednesday to 14,866, Xinhua said, but it was not immediately clear if that number included the 7,700 reported dead in Yingxiu.

In Sichuan province alone, 25,788 people were buried and 1,405 were missing, provincial vice governor Li Chengyun told Xinhua, which corrected an earlier report that 14,051 were missing.

Unlike previous natural disasters in China, state media has reported prominently on the quake. State television has cancelled regular programming to run 24-hour coverage.

Scenes of destruction and death have been shown, along with prominent focus on Premier Wen Jiabao, who rushed Monday to Sichuan to oversee the rescue work. He has been shown crawling into collapsed buildings to urge survivors to hang and reassuring children who have lost parents.

Wen was there when one three-year-old girl, trapped for more than 40 hours under the bodies of her parents, was pulled to safety Wednesday in Beichuan region, Xinhua said.

Rescuers found Song Xinyi on Tuesday morning, but were unable to pull her out right away due to fears the debris above her would collapse. She was fed and shielded from the rain until rescuers extricated her from the rubble.

Elsewhere, a 34-year-old woman who was eight months pregnant was rescued after spending 50 hours under debris in Dujiangyan.

"It's a miracle brought about by us all working together," said Sun Guoli, fire chief of the nearby provincial capital Chengdu, who supervised the rescue.

The show of official empathy was aimed at reassuring the public about the government's response and also showing the world the country is ready to host the Beijing Olympics in August.

Wednesday's leg of the Olympic torch relay in the southeastern city of Ruijin began with a minute of silence.

The death toll from the quake was expected to rise when rescuers reach other towns in Wenchuan county that remained cut off. Roads leading to Wenchuan from all directions were still being cleared of debris, Feng Zhenglin, deputy minister of railway and transportation, said in Beijing.

Many of the deaths have been students buried in schools. At a middle school Sichuan province's Qingchuan county, students were taking a noon nap when the quake demolished their three-storey building. A total of 178 of the children were confirmed dead in the rubble and 23 were missing, Xinhua said.

Relief efforts were aided Wednesday by the clearing of storms that had prevented flights over some of the worst-hit towns. Military helicopters were seen flying north over Dujiangyan, and Xinhua said two of them airdropped food, drinking water and medicine to Yingxiu.

Trains were on their way to Sichuan carrying quilts, drinking water, tents and military personnel, Ministry of Railways spokesman Wang Yongping said. All railways in the province were working except for a line where a 40-car freight train was trapped by a landslide in a tunnel and burned, he said.

East of the epicentre, in the town of Hanwang, the smell of incense hung over a crowd of sobbing relatives who walked among some 60 bodies wrapped in plastic, some covered with tributes of branches or flowers.

Nearby, rescuers in blue uniforms carried more bodies out of a makeshift morgue at the Dongqi sports arena. The dead appeared to have come from heavily damaged apartments and a school behind the arena, where people stood in stunned shock.

People from the town and surrounding areas packed into blue tents provided by relief officials. A western-style clock tower in the town centre was stopped at 2:27 - the time the quake hit.

The Mianzhu No. 3 Hospital was obliterated, and the seven-storey main Hanwang Hospital collapsed, its third floor suddenly smashing to the ground. People on the upper floors climbed out on bed sheets tied together.

Surviving medical staff set up a triage centre in the driveway of a tire factory, but could only provide basic care.

"The first day hundreds of kids died when a school collapsed. The rest who came in had serious injuries. There was so little we could do for them," said Zhao Xiaoli, a nurse at Hanwang Hospital, who described herself as "numb."

Emergency vehicle sirens sounded every few minutes. An ambulance drove in, delivering a man pulled from the rubble and covered in dust.

"There will be a lot more people. So many still haven't been found," said Zhao.