Bulugh al-Maram, Book 9, Hadith 1205 (In-Book)

Umm Salamah (RAA) narrated that The Messenger of Allah said: “The transgressing party will kill 'Ammar ('Ammar bin Yasir).” Related by Muslim.

وَعَنْ أَمِّ سَلَمَةَ رَضِيَ اَللَّهُ عَنْهَا قَالَتْ: قَالَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-{ تَقْتُلُ عَمَّارًا اَلْفِئَةُ اَلْبَاغِيَةُ } رَوَاهُ مُسْلِمٌ 1‏.‏ ‏1 ‏- صحيح رواه مسلم (2916)‏ (73)‏.‏

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also referenced under: Book 9, Hadith 1234 (English)