الجواب حامدا و مصلیا
If a place is officially declared as Waqf and a Masjid is built there it is considered a Shar’i Masjid which will be under the rule of Masjid upto the day of Qiyamath. To demolish the Masjid or using it for other purposes is, while being Haram and impermissible in Shari’a, it would tantamount to inviting the wrath and punishment of Allah, the Almighty. Therefore, it is incumbent and compulsory upon the influential personnel in the area to prevent the connected person or the institution from using the concerned place of the Masjid for some other purpose. It is permissible to take even legal action in the event they refuse to abide by.