Is it permissible to pray in a mosque located behind whose qiblah are graves at a distance of 3 kilometers from the company's site?

If the mosque was built for the sake of graves, then prayer in it is not permissible. However, if it was not built for that purpose, then prayer in it is permissible, provided that there is a barrier or wall separating the mosque from the graves. Some scholars have stipulated the presence of an open space or distance between them, or that the mosque's wall be high enough that the graves are not visible to the worshippers. If the mosque was built near graves for the purpose of glorifying them, then prayer in it is not permissible and it must be demolished.