The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1438

'Asim reported - I heard Anas saying: Never did I ace the Messenger of Allah (may peace be upon him) so much grieved (at the loss of a) small army as I saw him grieved at those seventy men who were called" reciters" (and were killed) at Bi'r Ma'una; and he invoked curse for full one month upon their murderers.

Source materials are from the University of Southern California MSA site
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