Riyad as-Salihin, Book 12, Hadith 1353 (In-Book)

Abu Hurairah (May Allah be pleased with him) reported: The Messenger of Allah said, "The martyrs are of five kinds: One who dies of plague; one who dies of disease of his belly; the drowned; one who dies under the debris (of construction, etc.), and one who dies while fighting in the way of Allah." [Al-Bukhari and Muslim].

وعن أبي هريرة رضي الله عنه قال‏:‏ قال رسول الله صلى الله عليه وسلم ‏:‏ ‏ "‏الشهداء خمسة‏:‏ المطعون والمبطون، والغريق، وصاحب الهدم والشهيد في سبيل الله‏" ‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏

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