The death toll at a mine in China's Henan province has risen to 26 as rescue teams try to free the 11 still trapped inside the shaft.
Family members waited outside the compound for news of their loved ones as police and mine officials gathered at the Pingyu Coal and Electric Co in Yuzhou City.
Rescue workers in orange suits made their way down the shaft in an attempt to reach those still trapped alive after an explosion inside the mine on Saturday.
Authorities said an over-concentration of underground gas caused the deadly explosion.
The underground gas concentration in the mine reached 40 per cent, over 40 times the normal level, according to state media.
Officials are quoted as saying that more than 2,500 tonnes of coal dust smothered the pit due to the explosion making it difficult for rescuers to go in.
239 workers have already managed to escape.
China's mines are the deadliest in the world, due to lax safety standards and a rush to feed demand from a robust economy. More than 2,600 people died in coal mine accidents in 2009 alone.
Another explosion at the same mine two years ago killed 23 people.