It is narrated from Abdullah bin Umar (may Allah be pleased with them both) that a Muslim deliberately killed a dhimmi, and the case came before Uthman (may Allah be pleased with him). He did not have him killed; rather, he imposed upon him blood money like the blood money of a Muslim.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنايات / 15931