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كتاب المغازى
64  
Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
(41)
Chapter: The sheep which qas poisoned (and presented) to the Prophet (saws) at Khaibar
(41)
باب الشَّاةِ الَّتِي سُمَّتْ لِلنَّبِيِّ صلى الله عليه وسلم بِخَيْبَرَ
Sahih al-Bukhari 4249

Narrated Abu Huraira:

When Khaibar was conquered, a (cooked) sheep containing poison, was given as a present to Allah's Apostle.

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، حَدَّثَنَا اللَّيْثُ، حَدَّثَنِي سَعِيدٌ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ قَالَ لَمَّا فُتِحَتْ خَيْبَرُ أُهْدِيَتْ لِرَسُولِ اللَّهِ صلى الله عليه وسلم شَاةٌ فِيهَا سُمٌّ‏.‏
Reference : Sahih al-Bukhari 4249
In-book reference : Book 64, Hadith 284
USC-MSA web (English) reference : Vol. 5, Book 59, Hadith 551
  (deprecated numbering scheme)