At least 91 people were missing after a giant mound of mud and construction waste spewed out of an overfull dump site in a southern China boomtown and buried 33 buildings in the country's latest industrial disaster.
The site should have been closed down in February, but according to local workers, mud and waste had continued to be dumped there, a news portal run by the city government in Shenzhen said.
Premier Li Keqiang ordered an official investigation into Sunday's landslide in Shenzhen, just across the border from Hong Kong. The mudslide smashed into multi-storey buildings at the Hengtaiyu industrial park in the city's northwestern Guangming New District, toppling them within seconds in collisions that sent rivers of earth skyward.
Villager Peng Jinxin said the mud came like "huge waves", as residents ran out of the way.
"At one point the running mud was only ten metres away from me," Peng told the official Xinhua news agency.
The frequency of industrial accidents in China has raised questions about safety standards following three decades of breakneck growth in the world's second-largest economy. Just four months ago, more than 160 people were killed in huge chemical blasts in the northern port city of Tianjin.
State television showed scenes of devastation in Shenzhen, with crumpled buildings sticking up from heaps of brown mud which stretched out across the industrial park.
Over a year ago, a government-run newspaper warned Shenzhen would run out of space to dump the waste left behind from a building frenzy.
Besides new buildings, a network of subway lines is being built in Shenzhen, and mounds of earth are being excavated and dumped at waste sites.
"Shenzhen has 12 waste sites and they can only hold out until next year," the official Shenzhen Evening Post, published by the city government, said in October, 2014.
Once a quiet fishing village, Shenzhen was chosen by Beijing three decades ago to help pioneer landmark economic reforms, and it has boomed ever since.
The mudslide at the business park had covered an area of more than 380,000 square metres (94 acres) and was 10 metres (11 yards) deep in parts, Shenzhen Vice Mayor Liu Qingsheng told reporters, according to Xinhua.
Almost 3,000 rescuers were at the scene, Xinhua said, with sniffer dogs and drones. Rescuers were focusing on several areas where sensors had detected signs of life, it added.
Unstable waste mountain
The Ministry of Land Resources said the accumulation of a large amount of waste meant that mud was stacked too steep, "causing instability and collapse, resulting in the collapse of buildings".
Local media said no foreign companies were believed to have been affected.
A nearby section of China's major West-East natural gas pipeline exploded, state television added, though it was not clear if this had any impact on the landslide.
Xinhua said the pipeline was owned by PetroChina, China's top oil and gas producer, that the 400-meter-long ruptured pipe "has been emptied" and a temporary pipe will be built.
PetroChina wrote on its microblog the pipeline blast had hit at least one industrial user, a Hong Kong power plant operated by Castle Peak Power Co Ltd, a company majority owned by a subsidiary of CLP Holdings, that has now switched to coal for power generation.
Fourteen factories, 13 low-rise buildings and three dormitories were among the buildings flattened.
Xinhua said 14 people had been rescued and more than 900 people had been evacuated from the site by Sunday evening.
State television said the 91 missing included 59 men and 32 women.