BOISE, Idaho -

A Washington state logging contractor who was using a bulldozer to cut fire line in central Idaho has died of an apparent heart attack or other natural causes.

Idaho Department of Lands officials say Dennis Long of Clarkston, Wash., was working Monday afternoon on the Pardee Fire northwest of Kamiah when he collapsed.

Long's boss performed CPR until emergency medical responders arrived. He was pronounced dead at the scene.

Long, who is in his early 50s, is survived by his wife and adult daughter.

The Pardee Fire was caused by lightning and grew to 55 acres Monday before calming down in the evening.