Sahih Muslim Book 16, Hadith Number 4126.
Abu Laila ‘Abdullah b. ‘Abd al-Rahman b. Sahl reported that the elderly persons of (the tribe) had informed Sahl b. Abu Hathma that ‘Abdullah b. Sahl and Muhayyisa went out to Khaibar under some distress which had afflicted them. Muhayyisa came and informed that Abdutlah b. Sahl had been killed, and (his dead body) had been thrown in a well or in a ditch. He came to the Jews and said: By Allah, it is you who have killed him. They said: By Allah, we have not killed him. He then came to his people, and made mention of that to them. Then came he and his brother Huwayyisa, and he was older than he, and ‘Abd al-Rahman b. Sahl. Then Muhayyisa went to speak, and it was he who had accompanied (‘Abdullah) to Khaibar, whereupon Allah’s Messenger (may peace be upon him) said to Muhayyisa: Observe greatness of the great (he meant the seniority of age). Then Huwayyisa spoke and then Muhayyisa also spoke. Thereupon Allah’s Messenger (may peace be upon him) said: They should either pay blood-wit for your companion, or be prepared for war. Allah’s Messenger (may peace be upon him) wrote about it to them (to the Jews). They wrote: Verily, by Allah, we have not killed him. Thereupon Allah’s Messenger (may peace be upon him) said to Huwayyisa and Muhayyisa and Abd al-Rahman: Are you prepared to take oath in order to entitle yourselves for the blood-wit of your companion? They said: No. He (the Holy Prophet) said: Then the Jews will take oath (of their innocence). They said: They are not Muslims. Allah’s Messenger (may peace be upon him), however, himself paid the blood-wit to them and sent to them one hundred camels until they entered into their houses, Sahl said: One red she-camel among them kicked me.