The Book of Zakat (Kitab Al-Zakat)

Muslim :: Book 5 : Hadith 2327

Abu Sa'id al-Khudri reported from the Apostle of Allah (may peace be upon him) that a group (Khwarij) would emerge from the different parties (the party of Hadrat 'Ali and the party of Amir Mu'awiya), the group nearer the truth between the two would kill them.

Source materials are from the University of Southern California MSA site
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