Sahih Bukhari Volume 4, Book 53, Hadith Number 369.
Narated By ‘Abdur-Rahman bin ‘Auf : While I was standing in the row on the day (of the battle) of Badr, I looked to my right and my left and saw two young Ansari boys, and I wished I had been stronger than they. One of them called my attention saying, “O Uncle! Do you know Abu Jahl?” I said, “Yes, What do you want from him, O my nephew?” He said, “I have been informed that he abuses Allah’s Apostle. By Him in Whose Hands my life is, if I should see him, then my body will not leave his body till either of us meet his fate.” I was astonished at that talk. Then the other boy called my attention saying the same as the other had said. After a while I saw Abu Jahl walking amongst the people. I said (to the boys), “Look! This is the man you asked me about.” So, both of them attacked him with their swords and struck him to death and returned to Allah’S Apostle to inform him of that. Allah’s Apostle asked, “Which of you has killed him?” Each of them said, “I Have killed him.” Allah’s Apostle asked, “Have you cleaned your swords?” They said, “No. ” He then looked at their swords and said, “No doubt, you both have killed him and the spoils of the deceased will be given to Muadh bin Amr bin Al-Jamuh.” The two boys were Muadh bin ‘Afra and Muadh bin Amr bin Al-Jamuh.