Chances of survival are slim for six miners who were left missing after the roof of a shaft collapsed in a small coal mine in central China's Hunan Province on Sunday, rescuers said.

The accident took place at around 1 PM on Sunday at Guanyin Coal Mine of Anping Township, Lianyuan City, when 48 miners were working in the shaft and 33 managed to escape, said Yan Yinchu, deputy director of the Provincial Coal Mine Safety Supervision Bureau.

Six miners were confirmed dead in the accident and three others were rescued and are receiving treatment in a local hospital, including one with serious gas poisoning. The injured people are not in danger, doctors said.

But the six missing miners have little chance of survival, rescuers said, adding that the complicated condition underground and excess amount of gas had delayed the rescue work.

The mine boss and a few managers fled after the collapse happened, Yan said, adding that they are trying increasing ventilation and other ways to lower the density of gas.

Guanyin Coal Mine is a township-administered coal mining venture capable of producing 30,000 tons of coal annually, but the mine's work safety license had been revoked before the accident and it has been ordered to suspend production, local authorities said.

(Xinhua News Agency December 5, 2006)