Sahih Bukhari Volume 009, Book 083, Hadith Number 019.
Narrated By Abu Huraira : In the year of the Conquest of Mecca, the tribe of Khuza'a killed a man from the tribe of Bam Laith in revenge for a killed person belonging to them in the Pre-lslamic Period of Ignorance. So Allah's Apostle got up saying, "Allah held back the (army having) elephants from Mecca, but He let His Apostle and the believers overpower the infidels (of Mecca). Beware! (Mecca is a sanctuary)! Verily! Fighting in Mecca was not permitted for anybody before me, nor will it be permitted for anybody after me; It was permitted for me only for a while (an hour or so) of that day. No doubt! It is at this moment a sanctuary; its thorny shrubs should not be uprooted; its trees should not be cut down; and its Luqata (fallen things) should not be picked up except by the one who would look for its owner. And if somebody is killed, his closest relative has the right to choose one of two things, i.e., either the Blood money or retaliation by having the killer killed." Then a man from Yemen, called Abu Shah, stood up and said, "Write that) for me, O Allah's Apostle!" Allah's Apostle said (to his companions), "Write that for Abu Shah." Then another man from Quraish got up, saying, "O Allah's Apostle! Except Al-Idhkhir (a special kind of grass) as we use it in our houses and for graves." Allah's Apostle said, "Except Al-idhkkir."