Hu Jintao, the president who is currently on a tour of earthquake-hit areas in neighbouring Shaanxi province, instructed local authorities to carry out search-and-rescue operations "immediately".
 
'Quake lake' drainage

The overall death toll from the earthquake, China's worst natural disaster in a generation, reached about 69,000 on Saturday with another 18,000 missing, the government said.

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China's fast response

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The incident came as more than one million people prepare to evacuate the region amid fears a lake created by the May 12 earthquake could burst.

The lake, formed when a huge landslide blocked the Jian River, has emerged as the most serious lingering threat to the region's residents, as it poses a flood risk to the area's large population.

Army and police crews finished digging a channel for the Tangjiashan "quake lake" that they hope will divert any floodwater and authorities said the rising waters could begin spilling into the channel on Sunday.

About 200,000 people had been evacuated in case of flooding,  officials said, but a total of 1.3 million are prepared to move, should the controlled release of water turn into a flood.

Authorities had originally planned to blast the blockage away with dynamite but feared that could cause all the rubble to give way, letting loose a deluge of water.

They hope to slowly drain away water in the lake, whose level has been rising by nearly two metres a day.

"About 1.3 million people are prepared for evacuation," said a disaster relief official in Mianyang city downstream from the lake.

"If the water drainage goes as planned peacefully, they won't have to."

Tangjiashan is the largest of more than 30 lakes that have formed behind landslides caused by the quake, which also weakened man-made dams in the mountainous parts of the disaster zone.

School safety

China has said it will conduct safety inspections of all schools in quake-hit areas of Sichuan, state media reported, after thousands of children were killed.

Over a 10-day period after the
quake, a Beichuan river swelled
by more than 60 hectares [AFP]
Countless school buildings collapsed when the 7.9-magnitude earthquake hit southwestern Sichuan province on May 12, killing thousands of pupils who were studying or taking naps.

In one school alone in Mianyang city, more than 1,300 children and teachers are dead or missing.

About 8,000 children were reported to be separated from their families in the first few days after the quake, though that figure has now been drastically reduced to 1,000, Ye Lu, a civil affairs department official, said.

"We are still getting thousands of calls per week asking about how to adopt, but we are still hoping to find the parents of these 1,000 kids," Ye said.

China's Red Cross has promised to release monthly audits of its relief operations to allay fears that aid money could be siphoned off by corrupt officials.

Jiang Yiman, China's Red Cross deputy director, said: "We will release the audit report every month.

"All money will be used for disaster relief, rescue and rebuilding efforts. No one should embezzle a penny."