What is the ruling on praying in a mosque that contains a shrine?

Question:
The questioner asks about a mosque next to a cemetery, where there is a grave separated by a room.

Answer:
If the cemetery is separated from the mosque by a street or open land, there is no harm. As for the structure built over a grave, a room built over a grave, it is obligatory to demolish it. The Messenger of Allah (peace and blessings be upon him) said, “Do not leave a raised grave except that you level it.” He said this to 'Ali ibn Abi Talib (may Allah be pleased with him): “Do not leave a raised grave, meaning one that is elevated with a structure built over it, except that you level it,” meaning you demolish the structure. This is because it is a cause for shirk (associating partners with Allah) and a means of shirk: the exaltation of graves and exaggeration regarding them.
It is obligatory for the one in authority, it is obligatory for the one in authority and the one who has power, to remove this structure from the grave. As for the one who has no power, his duty is only to explain the ruling and not to remove it with his own hand, because he does not have the authority to remove it by hand, as this would lead to bad consequences. Those who are responsible for removing structures from graves are the authorities, the people of power. As for the general public and those who have no power, their duty is only to explain, to explain that this is a matter that is not permissible and that it is a means of shirk. Yes.