وَحَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ عُمَرَ بْنَ عَبْدِ الْعَزِيزِ، قَضَى أَنَّ دِيَةَ الْيَهُودِيِّ، أَوِ النَّصْرَانِيِّ - إِذَا قُتِلَ أَحَدُهُمَا - مِثْلُ نِصْفِ دِيَةِ الْحُرِّ الْمُسْلِمِ ‏.‏ قَالَ مَالِكٌ الأَمْرُ عِنْدَنَا أَنْ لاَ يُقْتَلَ مُسْلِمٌ بِكَافِرٍ إِلاَّ أَنْ يَقْتُلَهُ مُسْلِمٌ قَتْلَ غِيْلَةٍ فَيُقْتَلُ بِهِ ‏.‏

Yahya related to me from Malik that he heard that Umar ibn Abdal-Aziz gave a decision that when a jew or christian was killed, hisblood-money was half the blood-money of a free muslim. Maliksaid, "What is done in our community, is that a muslim is not killedfor a kafir unless the muslim kills him by deceit. Then he is killedfor it." Translation Not Available

Book Ref: Muwatta Imam Malik Book 43 Hadith 1582
Web Ref:  Muwatta Imam Malik Book 43 Hadith 8