'Smoke' in the Bible

When the men of Ai turned back and looked, behold, the smoke of the city was ascending toward the sky, and they had no opportunity to run this way or that way. Then the people who had been running to the wilderness turned back toward the pursuers.

When Joshua and all Israel saw that the [men in] ambush had taken the city and that the smoke of the city was ascending, they turned back and struck down the men of Ai.