The accident took place at Xiahaizi coal mine in Qujing City on April 7, trapping 22 miners underground.
One miner is still missing, state-run Xinhua news agency reported.
Eleven local officials in charge of work safety have been removed or suspended from their posts, a spokesman with the Qujing municipal government said Sunday.
Previously, seven people, including the board chairman, the legal representative and the manager of the coal mine, have been detained by police.
Local authorities are investigating the cause of the accident.