It is narrated from Sayyiduna Ibn Amr (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: "Whoever kills someone intentionally shall be handed over to the heirs of the slain; if they wish, they may kill him in retaliation, and if they wish, they may accept blood money, which will consist of thirty Hiqqahs, thirty Jadh’ahs, and forty pregnant she-camels. This is the blood money for intentional murder. And whatever the two parties agree upon in reconciliation shall go to the heirs of the slain, and this is a severe blood money."
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 6717