China has issued an urgent appeal for earth-moving equipment to help rescue efforts in the country's south-west following Monday's earthquake.

On Thursday the confirmed death toll rose above 19,500, and the authorities say 26,000 people are believed to be buried under rubble in Wenchuan and other counties devastated by the quake.

Officials say rescue workers are sifting through the debris and searching for survivors with their bare hands, as time runs out to find survivors.

The government says it needs cranes, shovels and hammers.

Help accepted from Japan
After previously turning down international offers of help, including an offer of assistance from Australia, China gave permission on Thursday for a contingent of 60 Japanese rescue specialists and sniffer dogs to join the relief effort in Sichuan province.

Another aid team from Taiwan, including medical personnel, has also been accepted by Beijing.

Xinhua news agency says around 10 million people are severely affected by the aftermath of the earthquake, which is known to have killed nearly 15,000 people.

Damaged dams stabilised
Earlier, Water Resources Minister Chen Lei says the level of damage in Sichuan's many dams remains "unclear".

"China faces prominent problems in safety and flood prevention at reservoirs, hydropower stations, dammed lakes and other facilities in the quake zone," he was quoted by Xinhua as saying.

Xinhua reports that spillways have been opened at the Zipingpu Dam near the quake's epicentre to release water, after the quake left it cracked in several places.

Chinese authorities say the dam is now safe.

A separate state media report said a swelling river, blocked by a landslide triggered by the quake, was threatening to swamp rescue teams racing to free victims of the disaster.

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