Water is pumped out of the Wangjialing Coal Mine in Shanxi province on Wednesday. [Xinhua]

A failure to heed warnings that water was seeping into the coal shaft and a slow evacuation led to 153 miners becoming trapped Sunday in a mine in north China's Shanxi Province, officials said Wednesday.

An evacuation should have been ordered immediately after managers received reports of water leakage, said Luo Lin, director of the State Work Safety Administration (SWSA).

Managers should have evacuated miners, cut the power and suspended work at once, he said. "The response should have been much faster."

Workers at the Wangjialing Coal Mine had warned supervisors twice late Sunday morning, about two hours before the flood occurred, said Jiang Shijie, a manager of the Wangjialing coal mine project.

Jiang received an emergency phone call at about 1:40 p.m. that water was pouring into the shaft. He tried to contact miners underground to raise the alert, but could not reach them.

Workers told Xinhua that they noticed water coming in even earlier -- several days before the disaster occurred.

"We found water leaks on March 25 and reported them to management, but there was no response," said a worker who declined to be named.

Another worker surnamed Chen said he refused to enter the pit Saturday after because digging had stopped causing dust. "That was the sign the flood was coming."

Altogether 261 workers were in the pit when underground water gushed in at about 1:40 p.m. Sunday. A total of 108 were lifted to the ground while 153 were trapped.

An initial investigation showed the project management failed in water detection and release, resulting in workers breaking through to an adjacent disused shaft that was full of water, said a statement from the SWSA.

The statement said as many as 14 teams were working underground to accelerate the project, so that a large number of workers were trapped.

A worker from central China's Hubei Province said work speed seemed to be the only order from the management, and safety was barely mentioned.

The flood water had dropped, but there was still no communication with those trapped as of 1 p.m. Wednesday although almost 1,000 rescuers have been racing against the clock to pump out water and try to reach them.

The mine, affiliated to the state-owned Huajin Coking Coal Co. Ltd., is a major project approved by the provincial government. It is expected to produce 6 million tonnes of coal annually once in operation.