The mishap happened while miners were working to seal off a conflagration, local officials said.
The cause of the accident is still unknown, as the toxic gas concentration in the shaft has exceeded the standard limit, preventing rescuers from going down the shaft, they said.
All the injured were hospitalised and an investigation over the cause of the accident is underway.
On Tuesday, it was reported a coal mine blast has trapped seven miners in northeast China's Heilongjiang Province on Monday.
Coal mine accidents killed 357 people in China, the world's largest coal producer and consumer, in the first two months of this year, the government said recently.
It said 4,746 people died in 2,845 coal mine accidents last year, an average of 13 deaths a day.