Twenty-nine miners are believed to be trapped after a gas explosion at a coal mine in northwest China's Shaanxi Province late yesterday.

The blast occurred at around 8 p.m. at in the shaft at the Yaotou mine in Chengcheng county, in central Shaanxi, and emergency workers launched a rescue operation shortly after, said a provincial government spokesman.

The blast was reported to officials shortly after it occurred and the provincial government reported it to the State Administration of Work Safety the same evening, said the spokesman.

No further details were yet available, he said.