Ibrahim narrated from Sayyiduna Ibn Mas'ud (may Allah be pleased with him) concerning a man from whom retaliation is taken and who then dies, that he said: "The one who took retaliation owes his (the deceased's) blood money, then the blood money for his (own) wound is deducted from it."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 9699