Mishkat al-Masabih 142
Ibn ‘Abbas reported God’s messenger as saying, “The people most hateful to God are of three classes:
he who is heretical in the sacred territory, he who wants to introduce into Islam the sunna of the pre-Islamic period, and he who unjustly demands the death of a Muslim to shed his blood.” 

Bukhari transmitted it.
وَعَنِ ابْنِ عَبَّاسٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «أَبْغَضُ النَّاسِ إِلَى الله ثَلَاثَة ملحد فِي الْحرم وميتغ فِي الْإِسْلَام سنة الْجَاهِلِيَّة ومطلب دم امرىء بِغَيْر حق ليهريق دَمه» رَوَاهُ البُخَارِيّ