We raided a clan of Juhaynah, and one of the Muslims pursued a man from among them. He struck at him but missed, and the sword instead struck himself.The Messenger of Allah ﷺ said, "Muslims, tend to your brother."The people rushed to him and found that he had died. The Messenger of Allah ﷺ wrapped him in his clothes along with his blood, prayed over him, and buried him.They asked, "Messenger of Allah, is he a martyr?"He replied, "Yes, and I bear witness to it for him."
حدثنا هشام بن خالد الدمشقي حدثنا الوليد عن معاوية بن أبي سلام عن أبيه عن جده أبي سلام
أغرنا على حي من جهينة فطلب رجل من المسلمين رجلا منهم فضربه فأخطأه وأصاب نفسه بالسيف فقال رسول الله ﷺ أخوكم يا معشر المسلمين فابتدره الناس فوجدوه قد مات فلفه رسول الله ﷺ بثيابه ودمائه وصلى عليه ودفنه فقالوا يا رسول الله أشهيد هو قال نعم وأنا له شهيد
No references are available.
Its isnad is daif. Bayhaqi 8/110 narrated it from the hadith of Abu Dawud, with the same chain.Walid bin Muslim did not explicitly state that he heard it directly throughout the chain, and Salam bin Abu Salam is unknown (Taqrib).