Working in China's coal mines is becoming more dangerous a report released by the State Administration of Work Safety (SAWS) states.

"There is a stronger demand for coal in the winter as it's the major material for heating in most parts of China," said a SAWS official. "For this reason coal mines try to produce more than they can manage."

Three of the four serious incidents have occurred in north China's Shanxi province, the country's major coal production area, which is notorious for its frequent accidents.

A gas blast in a coal mine in Shanxi on November 12 killed 25 people and nine others remain missing.

Another accident in Shanxi on November 5 left 35 dead and 12 missing. Two-and-a-half hours earlier the monitoring system showed the gas concentration was abnormal and there was a risk of explosion, according to the SAWS. But the production managers didn't take effective measures or order the miners to stop working, it said.

The administration urged coal mines to strictly follow rules of operation and local governments to crack down on illegal operations.

(Xinhua News Agency November 14, 2006)