Hope fading for quake survivors

Hope is fading for thousands of people in China who are still thought to be trapped under collapsed buildings, five days after a deadly earthquake struck.

So far, nearly 20,000 people are known to have died, but it's feared that number may rise to more than 50,000.

China's president Hu Jintao has flown to one of the worst hit cities in the Sichuan region to see what's going on.

He said the rescue work had entered its most crucial phase as troops continued to search for survivors.

Click here to see pictures of the quake area

Chinese president Hu Jintao

"The challenge is still severe, the task is still arduous and the time is pressing," said Mr Hu.

"We must make every effort, race against time and overcome all difficulties to achieve the final victory of the relief efforts."

About 10 million people in China have been directly affected by the quake, which devastated large parts of the Sichuan province on Monday.

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About 80,000 troops are already involved with the huge rescue operation, and now the first rescuers from other countries are starting to arrive.

The darker colours show the worst hit parts of the Sichuan province

Head of the Chinese Government Wen Jiabao said: "Saving lives is still our top priority, as long as hope of survival still exists."

But it's a massive job. At least 200,000 houses are said to have collapsed in Sichuan province, with more than four million others damaged in some way.

Click here for our guide to earthquakes

Elsewhere, soldiers have also been trying to repair dangerous cracks in a dam which is letting out loads of water, up the river from the earthquake-hit city of Dujiangyan.

The dam is a thick wall that holds back loads of water to form a reservoir, stopping villages and towns further down the river from flooding.

Tremors

The quake is the most powerful one to hit China for 30 years. It struck near the city of Chengdu on Monday and reached 7.8 on the Richter scale, which measures tremors.

The scale goes up to 10, so this was a big quake which was felt as far away as Beijing, 930 miles away, and the Thai capital, Bangkok.