The gas leak at the Sizhuang coal mine in Shizong county occurred last Thursday, initially killing 20 people and leaving 23 trapped.

It is believed the gas leak happened at one platform inside the shaft and later spread to another platform inside the mine.

Government spokesman Li Jianjun said 34 people were confirmed dead at 9.30am Sunday morning and nine men were still trapped in the mine, according to Xinhua, .

Li told Xinhuathere were over 100 rescuers searching for the remaining trapped men, but warned the risk of large amounts of gas underground could hamper the rescue operation.

According to China Daily, the Sizhuang mine was operating without a mine license after it was revoked a year ago.

Meanwhile seven miners remain trapped at the Sigeshan Tongda coal mine after flooding occurred early Sunday morning in the country’s Gansu province.

Local reports said rescuers were pumping water out of the coal mine in an effort to reach the trapped miners.