Bukhari 59:447

Narrated Abu Said Al-Khudri:

The people of (Banu) Quraiza agreed to accept the verdict of Sad bin Mu'adh. So the Prophet sent for Sad, and the latter came (riding) a donkey and when he approached the Mosque, the Prophet said to the Ansar, "Get up for your chief or for the best among you."

Then the Prophet said (to Sad). "These (i.e. Banu Quraiza) have agreed to accept your verdict."

Sad said, "Kill their (men) warriors and take their offspring as captives, "On that the Prophet said, "You have judged according to Allah's Judgment," or said, "according to the King's judgment."