An excavator is seen at the spot of the mud-rock flow in Xiangfen County, Linfen City, north China's Shanxi Province, Sept. 12, 2008. The death toll from the rain-triggered mud-rock flow, occurring on Monday in a pond holding waste ore dregs of the local Tashan Mine, rose to 178 on Friday. Some 268,000 cubic meters of sludge deluged over an area of 30.2 hectares in the disaster.

Rescuers carry the body of a victim onto the ambulance at the spot of the mud-rock flow in Xiangfen County, Linfen City, north China's Shanxi Province, Sept. 12, 2008.

TAIYUAN, Sept. 12 (Xinhua) -- The death toll from a rain-triggered mud-rock flow in north China's Shanxi Province rose to 178 as of 5 p.m. on Friday, the local rescue headquarters said.

The accident occurred around 8 a.m. on Monday in a pond holding waste ore dregs of the Tashan Mine in Xiangfen County, Linfen City, which was soaked by torrential rain.

In total, 268,000 cubic meters of sludge deluged over an area of 30.2 hectares.

The State Council, China's Cabinet, set up an accident investigation team, including officials from the State Administration of Work Safety, Shanxi provincial government, Ministry of Supervision, Ministry of Land and Resources, and All China Federation of Trade Unions.

Such an investigation team is set up for a "very severe accident", those which have caused at least 30 deaths, or severe injuries to at least 100 people, or 100 million yuan loss or above, according to State Council regulation.

Shanxi Provincial Government Secretary-General Wang Qingxian said about 90 percent of the area had been combed. Altogether 2,200 rescuers, using more than 110 excavators, were hunting for survivors.

An initial investigation revealed the accident's cause was "the unlicensed Tashan mine operated illegally and the stored waste iron ore dregs had surpassed the capacity of the holding pond," said the rescue headquarters.