Sunan Abi Dawud, Hadith 3012

Ibn Shihab said “It has reached me that the Apostle of Allaah conquered Khaibar by force. Its inhabitants who came down (from their fortress) for expulsion came down after fighting.”

حَدَّثَنَا ابْنُ السَّرْحِ، حَدَّثَنَا ابْنُ وَهْبٍ، أَخْبَرَنِي يُونُسُ بْنُ يَزِيدَ، عَنِ ابْنِ شِهَابٍ، قَالَ بَلَغَنِي أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم افْتَتَحَ خَيْبَرَ عَنْوَةً بَعْدَ الْقِتَالِ وَنَزَلَ مَنْ نَزَلَ مِنْ أَهْلِهَا عَلَى الْجَلاَءِ بَعْدَ الْقِتَالِ ‏.‏

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also referenced under: Hadith 3018 (DarusSalam)