A blast at China's Liushenyu coal mine in Shanxi province kills at least 82 people, raising questions about the safety costs of the country's coal production drive.

A gas explosion at the privately owned Liushenyu mine in Shanxi province on Friday night left at least 82 dead, making it the deadliest mining disaster in years.

The Liushenyu mine produces mostly coking coal, which supplies steelmakers rather than power plants, and is a midsized operation producing a fraction of the region's annual total.

The incident is already prompting a government response despite the mine's relatively small scale, raising uncomfortable questions about the human cost of China's world-beating coal production.