Four miners were suffocated and one was reported missing following a build-up of poisonous gas in a coal mine in central China's Hubei Province, local work safety officials said Monday.

The accident happened around 9:43 a.m. Monday at the Wangzigou colliery in Zigui County when ventilation equipment in the mine stopped working, said the Yichang City Work Safety Administration.

As of 11 p.m., four had been confirmed dead while one was still missing.

The colliery is licensed with an approved annual capacity of 10,000 tons. It was upgrading facilities and planned to raise its capacity to 30,000 tons in the second half of this year.

The cause of the accident is still being investigated.

(Xinhua News Agency January 8, 2008)