'Smoke' in the Bible

Then the men of Ai, looking back, saw the smoke of the town going up to heaven, and were unable to go this way or that: and the people who had gone in flight to the waste land were turned back on those who were coming after them.

And when Joshua and all Israel saw that the town had been taken by the surprise attack, and that the smoke of the town had gone up, turning round they overcame the men of Ai.