SHIZONG, Yunnan - Thirty-four miners have been confirmed dead after a gas leak occurred in a coal mine in southwest China's Yunnan province Thursday morning, rescue headquarters said Sunday.

As of 9:30 am Sunday, 34 bodies have been found, and nine miners are still trapped underground at Sizhuang Coal Mine, located in the county of Shizong near the city of Qujing, according to Qujing government spokesman Li Jianjun.

Hundreds of rescuers are continuing to search for the trapped miners, Li said. He said another 181-meter-long section of the tunnel has yet to be cleared, warning that a risk of large amounts of gas underground would hamper the operation.

The mine was operating illegally, having had its license revoked a year ago, according to a statement from the provincial coal safety supervision bureau. The bureau ordered the mine to stop production in April.