Musnad Ahmad 1226:2

Yahya ibn Sa'id narrated to us, he said: Ibn Abi Dhi'b narrated to us, he said: Sa'id—meaning al-Maqburi—narrated to us, he said: I heard Abu Shurayh al-Ka'bi say: The Messenger of Allah (peace and blessings of Allah be upon him) said on the day of the conquest of Makkah: "Indeed, Allah the Almighty and Majestic has made Makkah sacred, and people have not made it sacred. So whoever believes in Allah and the Last Day, let him not shed blood therein, and let him not cut down trees therein. If anyone seeks a concession, saying: 'It was made lawful for the Messenger of Allah (peace and blessings of Allah be upon him),' then [say to him]: 'Indeed, Allah made it lawful for me and did not make it lawful for the people, and it is sacred at this hour of mine until the Hour is established.' "Indeed, you, O group of Khuza'ah, have killed this person, and I am the one who will pay the blood money for him. So whoever has a person killed after this statement of mine, his family has two choices: either they kill, or they take the blood money."