Office of Grand Ayatollah Khamenei (may Allah grant him long life)

If the said graveyard is not a part of an endowed piece of land or a private property and it is not either a public place which is needed and used by people on various occasions and if building a mosque does not lead to desecration of Muslims or exhumation of their graves, there is no problem.

Office of Grand Ayatollah Sistani (may Allah grant him long life)

If the land is not endowed for burial purposes, there is no problem in it.

Office of Grand Ayatollah Makarem Shirazi (may Allah grant him long life)

A mosque can be built on a graveyard only when burying dead bodies is not allowed in it or when it does not lead to exhumation of the graves especially those of religious scholars. However, offering prayers in that mosque is permissible under all circumstances. Also, you should note that if the land has been endowed for graveyard, it should be used only for the same purpose except for when due to some reason burial is not possible there in which case they can sell the land and use its money for purchasing land for graveyard. The purchased land should be turned into Waqf (endowment) property. In case they have enough graveyard, they can use the land to build a mosque, Hussainiyah, library and such likes.

The answer given to the question by His Eminence, Ayatollah Mahdi Hadavi Tehrani is as under:

If the land is not endowed specifically for graveyard and if the mosque is built in such a way that it does not hinder burial (for example, it is built at a higher place), and there is also no prohibition on the part of the endower, there is no problem in constructing a mosque there. Of course, if the land is endowed specifically for burial and building a mosque hinders burial, it is not permissible to build a mosque in the graveyard. In case, for some reason the land can no longer be used as graveyard, i.e. it is close to a residential area and it is likely that pollution may spread out to other places, the land that cannot be used for graveyard can be used, with the permission of a qualified jurist, to construct a mosque in it.

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