Judges 20:36-39

³⁶But the children of Benjamin when they saw themselves to be too weak, began to flee. Which the children of Israel seeing, gave them place to flee, that they might come to the ambushes that were prepared, which they had set near the city.

³⁷And they that were in ambush arose on a sudden out of their coverts, and whilst Benjamin turned their backs to the slayers, went into the city, and smote it with the edge of the sword.

³⁸Now the children of Israel had given a sign to them, whom they had laid in ambushes, that after they had taken the city, they should make a fire: that by the smoke rising on high, they might shew that the city was taken.

³⁹And when the children of Israel saw this in the battle (for the children of Benjamin thought they fled and pursued them vigorously, killing thirty men of their army)