Hadith 6:998
Sharik narrated to us, from Abu Fazara, from a freed slave of Ibn Abbas, who said: Ibn Abbas said to me: "When you see that a people have buried a dead person and have introduced into his grave that which is not in the graves of the Muslims, then level it to the graves of the Muslims."
حدثنا شريك عن أبي فزارة عن مولى لابن عباس قال قال لي بن عباس إذا رأيت القوم قد دفنوا ميتا فاحدثوا في قبره ما ليس في قبور المسلمين فسوه بقبور المسلمين