1.   Scientists could not explain why the gas had suddenly ignited.

2.   An employee of Performance Oilfield Service of Kilgore was injured when the gas ignited during work on the well, Dalton said.

3.   Duncan said the miners were lengthening a major access tunnel to a working area when the gas, probably methane, ignited.

4.   However, it was still unclear why the gas ignited.

5.   Some sniffers die or are horribly burned in accidents when gas ignites.

6.   The fire apparently started when gas from a lawn mower ignited.

7.   The flame went out before the gas ignited, police said.

8.   The officials, speaking on condition of anonymity, said the explosion occurred when gas leaking from a cylinder ignited.