Bulugh al-Maram, Book 11, Hadith 1292 (In-Book)

'Auf bin Malik (RAA) narrated, “The Messenger of Allah judged that the belongings taken from the (non-Muslim enemy) killed soldier in a war, are to be given to the one who killed him.' Related by Abu Dawud. Muslim reported it as part of a long hadith.

وَعَنْ عَوْفِ بْنِ مَالِكٍ ‏- رضى الله عنه ‏- { أَنَّ اَلنَّبِيَّ ‏- صلى الله عليه وسلم ‏-قَضَى بِالسَّلَبِ لِلْقَاتِلِ } رَوَاهُ أَبُو دَاوُدَ 1‏.‏ وَأَصْلُهُ عِنْدَ مُسْلِمٍ 2‏.‏ ‏1 ‏- صحيح.‏ رواه أبو داود ( 2719 )‏ في حديث طويل.‏ ‏2 ‏- صحيح.‏ رواه مسلم ( 1753 )‏ ( 44 )‏.‏

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also referenced under: Book 11, Hadith 1319 (English)