Narrated Ibn ‘Abbas (radiyallaahu-anhumaa):

The Prophet said, “The most hated persons to Allah are three: (1) A person who deviates from the right conduct, i.e., an evil doer, in the Haram (sanctuaries of Mecca and Medina); (2) a person who seeks that the traditions of the Pre-lslamic Period of Ignorance, should remain in Islam (3) and a person who seeks to shed somebody’s blood without any right.” [Saheeh Al-Bukhaari, Hadeeth Number 21, Vol 9]