From Sahih Bukhari (Hadith 4766):
Narrated Sa`id bin Jubair:`Abdur-Rahman bin Abza ordered me to ask Ibn `Abbas regarding the two Verses (the first of which was ): "And whosoever murders a believer intentionally." (4.93) So I asked him, and he said, "Nothing has abrogated this Verse." About (the other Verse): 'And those who invoke not with Allah any other god.' he said, "It was revealed concerning the pagans
Reference: Bukhari 4766