Is it permissible to perform funeral prayers for multiple deceased persons simultaneously?

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It is permissible for the funeral prayer (Salat al-Janazah) to be performed for multiple deceased persons in a single instance. An instance of performing the prayer for each deceased individually is also permissible. It is narrated that the Prophet, peace be upon him, prayed over Hamza along with others. Ahmad's apparent preference, consistent with the practice of the early Muslims, leans towards performing a separate prayer for each body unless there is a need to expedite the burial.