Judges 20:36-39

36So the people of Benjamin saw that they were defeated. The men of Israel gave ground to Benjamin, because they trusted the men in ambush whom they had set against Gibeah. 37Then the men in ambush hurried and rushed against Gibeah; the men in ambush moved out and struck all the city with the edge of the sword. 38Now the appointed signal between the men of Israel and the men in the main ambush was that when they made a great cloud of smoke rise up out of the city 39the men of Israel should turn in battle. Now Benjamin had begun to strike and kill about thirty men of Israel. They said, “Surely they are defeated before us, as in the first battle.”