Professional rescuers were still searching for six miners trapped at a coal mine in central China's Hubei Province after a gas outburst on Friday morning.

The accident occurred at 8:20 a.m. when six miners were in the Dakuaitian colliery in Zigui County, Yichang City. They were trapped at a depth of 70 meters.

The miners, all male, were in their 30s and 40s.

According to the rescue headquarters, when the blast occurred, about 500 tonnes of coal was affected. The gas density remained above the safety limit in the pit.

It was believed there were some explosives and detonators at the scene, which threatened secondary disasters as well as hampering the rescue efforts.

The county government had sealed all the files and documents of the coal mine. An investigation was underway.

All the coal mines in the county had been ordered to suspend operation.

The fully-licensed mine has 37 staff members.

(Xinhua News Agency August 2,2008)