A large aftershock hit China's Sichuan province Saturday and thousands of people fled the epicentre, afraid the latest tremor would cause blocked rivers to burst their banks.
The 5.7-magnitude temblor -- earlier measured at 6.1 -- hit the province five days after a massive earthquake caused widespread death and destruction. It was also the second aftershock in as many days.
The U.S. Geological Survey reports that Saturday's quake hit about 80 kilometres below the surface and about 78 kilometres west of Guangyuan.
There were no immediate reports of additional damage or casualties, although the aftershock temporarily put relief efforts on hold. Thousands of people evacuated the area, afraid the tremor would shake loose landslides that had blocked various rivers and cause them to flood.
"I'm very scared. I heard that the water will be crashing down here," Liang Xiao, one of the people fleeing, told The Associated Press. "If that happens, there will be over 10 yards of water over our heads."
The latest temblor struck as the official death toll neared 29,000 from Monday's 7.9-magnitude quake.
Chinese soldiers carried some seniors out of Beichuan town, one of the communities hit hardest by Monday's magnitude-7.9 earthquake.
A policeman told The Associated Press that rescue officials worried that water from the choked river would inundate the town.
"The river was jammed up by a landslide, now that may burst. That is what we are worried about," the policeman said as he hurried by, not giving his name.
Earlier, Xinhua, the official Chinese news agency, had said a Beichuan county lake "may burst its bank at any time." No details were given on why waters were rising.
ABC News reporter Stephanie Sy told CTV Newsnet from China that the lake had not burst, but the flood threat in the mountainous region is real.
In the town of Qingchuan north of Beichuan, Xinhua said more than 2,000 people were being evacuated. The Qingzhu river was blocked by quake-related slides.
"They've evacuated more than a million people from one of the towns close to the epicentre," Sy said.
A Chinese cabinet spokesman said the confirmed death toll is now 28,881.
Survivors still found
Although time is the enemy, survivors are still being found. Rescuers pulled a 52-year-old man to safety in Beichuan, and a German tourist was found alive in Wenchuan county.
More than 100 other survivors have been found, "which is quite extraordinary, given that some of them have been buried with no food or water for five days," Sy said.
Close to 11,000 people remain buried in Sichuan province, Xinhua cited regional government officials as saying.
Aftershocks are rattling unstable buildings, making things dangerous for rescuers.
Rescuers from South Korea, Singapore and Russian joined the search effort on Saturday. A Japanese crew is already in the area.
The United Nations has authorized a grant of up to $7 million from its Central Emergency Response Fund. UN agencies and programs can use the money to help fund relief efforts.
A U.S. Air Force jet left Hawaii on Saturday, carrying tents, lanterns and 15,000 meals to help relief efforts in Sichuan.
The town square of Shifang, north of the provincial of Chengdu, currently serves as a tent camp for 2,000 people. But there is a shortage of tents.
"We brought almost nothing, only the clothes we are wearing," said Zhang Xinyong, a high school junior.
Housing Minister Jiang Weixing said more than four million apartments or homes have been damaged in Sichuan provinces.
The water supply situation there was "extremely serious," he said.
There have been no major disease or other such public health problems in the earthquake zone so far, Xinhua said.
With files from The Associated Press
