וְזֶ֥ה הַדָּבָ֖ר אֲשֶׁ֣ר תַּעֲשׂ֑וּ כָּל־זָכָ֗ר וְכָל־אִשָּׁ֛ה יֹדַ֥עַת מִשְׁכַּב־זָכָ֖ר תַּחֲרִֽימוּ׃
And this is the thing that ye shall do: ye shall utterly destroy every male, and every woman that hath lain by man.’
Read halakhic rulings (Jewish law) on Judges 21:11: and classical halakhic sources.