What is the ruling on donating to build a mosque on land where graves were previously located and then moved to another place?

The permissibility of exhuming graves and building a mosque in their place depends on a legitimate Sharia interest. If there is a need for it, such as the unavailability of a more suitable location for expanding the mosque, then it is permissible to exhume the graves and transfer the remains to the public cemetery. As for the graves of non-Muslims, they may be exhumed absolutely when there is a need. Donating and participating in building a mosque on such land is an act of righteousness if the exhumation is permissible.