Sahih Bukhari Volume 008, Book 078, Hadith Number 698.

Narated By Abu Huraira : We went out in the company of Allah's Apostle on the day of (the battle of) Khaibar, and we did not get any gold or silver as war booty, but we got property in the form of things and clothes. Then a man called Rifa'a bin Zaid, from the tribe of Bani Ad-Dubaib, presented a slave named Mid'am to Allah's Apostle. Allah's Apostle headed towards the valley of Al-Qura, and when he was in the valley of Al-Qura an arrow was thrown by an unidentified person, struck and killed Mid'am who was making a she-camel of Allah's Apostle kneel down. The people said, "Congratulations to him (the slave) for gaining Paradise." Allah's Apostle said, "No! By Him in Whose Hand my soul is, for the sheet which he stole from the war booty before its distribution on the day of Khaibar, is now burning over him." When the people heard that, a man brought one or two Shiraks (leather straps of shoes) to the Prophet. The Prophet said, "A Shirak of fire, or two Shiraks of fire."