An explosion at a coal mine in southwest China has killed nine people in the latest deadly incident to hit the country's mining industry, state media has reported.

One other miner was reported missing after the blast at the mine in Guizhou province, China's state-run Xinhua news agency said.

The accident occurred less than a week after another explosion at a mine in northeastern China left at least 107 dead.

The cause of the latest incident on Thursday evening was not given, although such explosions usually result from a failure to ventilate coal gas that builds up deep in the pit.

According to state media, investigators probing last Saturday's explosion in a mine outside the city of Hegang have blamed crowded conditions, insufficient ventilation and slow rescue efforts for the high death toll.

The explosion was the deadliest accident at a Chinese mine in more than two years.

Despite repeated efforts to improve safety standards and close the most dangerous mines, China's coal industry remains the world's deadliest.

According to the government mining accidents claimed 1,175 lives in the first six months of this year, an 18.4 per cent drop over the same period last year.