The Messenger of Allah ﷺ said, "Listen, people of Khuza, you have killed this man from Huzayl, and I will pay his blood-money. But anyone whose relative is killed after this statement of mine, his family has a choice between two options. They may take the blood-money, or they may kill the killer."
قال رسول الله ﷺ: ألا إنكم معشر خزاعة قتلتم هذا القتيل من هذيل، وإني عاقله. فمن قتل له بعد مقالتي هذه قتيل فأهله بين خيرين. أن يأخذوا العقل، أو يقتلوه.
Reported by Abu Dawud (4504), Tirmidhi (1439), Ahmad (27160), and Daraqutni (3/95-96), all of them from the hadith of Yahya bin Saeed, who said, Ibn Abu Dhib narrated to us, who said, Saeed Maqburi narrated to us, who said, I heard Abu Shurayh Kaabi, and then he related it. Its chain of transmission is sahih. Tirmidhi said, "This is a hasan sahih hadith."Abu Shurayh Kaabi has another hadith in the Sahihayn about the prohibition of shedding blood, within a long account concerning the virtues of Makkah.