Hazrat Nafi’ narrates that Hazrat Ibn Umar (may Allah be pleased with them) said: A slave-girl of Hazrat Hafsa practiced magic on her, and people found her performing magic, and she also confessed to it. Hazrat Hafsa ordered Hazrat Abdur Rahman bin Zaid, so he killed her. When this news reached Hazrat Uthman, he did not like it and expressed his anger over it. So Hazrat Ibn Umar (may Allah be pleased with them) came to him and informed him that indeed she had practiced magic on you, and people had also found her performing magic, and that sorceress had also confessed to it. Thus, it seems Hazrat Uthman disliked this because she was killed without his permission.