A gas leak killed 29 coal miners Thursday in southwest China, while another six are missing and presumed dead, state media said.
Xinhua News Agency said the accident happened at the Qunli mine in Nayong county in Guizhou province.
It said rescue workers had recovered 28 bodies. Fifty-two miners were rescued, but one later died.
"The other six miners have a slim chance of survival," Xinhua said.
The cause of the gas leak was not immediately known.
The government warned recently that China's mining industry, the most dangerous in the world, would likely see more accidents as output was boosted to provide heating for the winter months.
China's coal mines average 13 deaths a day in fires, explosions and floods, despite government efforts to improve safety.
In August, 181 miners died when two mines flooded in eastern Shandong province after heavy rains.
Many of the accidents are blamed on mine owners who disregard safety rules and fail to invest in required ventilation, fire control and other equipment.