It is narrated from Sayyiduna Ali (may Allah be pleased with him) that he addressed his companion Abu’l-Hayyaj Asadi and said: I am sending you for the task for which the Prophet (peace and blessings be upon him) sent me. He commanded me to level every grave and to obliterate every idol.
Hadith Referenceمسند احمد / مسند الخلفاء الراشدين / 741