Millions affected by deadly quake

About 10 million people in China have been affected by the earthquake which has flattened entire villages in the south-west, according to authorities.

Another 30,000 troops are being sent to help the 50,000 already involved with the rescue operation since the quake hit the Sichuan province on Monday.

Nearly 20,000 people are known to have died, with thousands more still missing or trapped under collapsed buildings.

The extra troops are bringing food and water, and helping to rescue survivors.

Click here to see pictures of the quake area

Check out the damage to the town of Yingxiu in Wenchuan County. Enlarge Image

The Chinese military is also planning lots of airdrops of food, clothing and blankets over the worst-hit areas, including the districts of Beichuan and Wenchuan.

The helicopters are needed because many of the roads in the mountainous area near the centre of the quake have been badly damaged or covered by landslides.

Rescuers have also been held up by bad weather. The quake was the most powerful one to hit China for 30 years and officials fear it may have killed more than 50,000 people.

But survivors are still being found. On Wednesday, a three-year-old girl and a pregnant woman were among those who were saved.

Click here for our guide to earthquakes

Meanwhile, thousands of families who've been made homeless are having to sleep in the open air or in temporary shelters that line the streets where their homes used to be.

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

The Chinese government says it's accepting help from other countries, but also appealed to the public to donate basic equipment, like hammers and shovels, to help with the rescue operation.

Elsewhere, soldiers have also been trying to repair dangerous cracks in a dam which are 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 hit near the city of Chengdu on Monday afternoon 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.