What is the ruling on announcing deaths via loudspeakers in mosques, and what is the correct way to make such an announcement?

It is permissible to inform people of a person's death, as long as it is not accompanied by any religiously prohibited act. The proof for this is that the Prophet, peace and blessings be upon him, said concerning the Black man who died without his knowledge, "Why did you not inform me?"

However, it is not appropriate to announce funerals with loudspeakers in the mosque. Imam Malik disliked announcing a funeral in the mosque or making noise about it. Nevertheless, there is no harm in people informing one another of a death without raising their voices.