Sunnah.com reference : Book 9, Hadith 33English translation : Book 9, Hadith 1230Arabic reference : Book 9, Hadith 1201
Sahl bin Abi Khaithamah (RAA) narrated on the authority of some honored men from his people that 'Abdullah bin Sahl and Muhaiysah bin Mas'ud, went out to Khaibar because of a hardship they were undergoing. Muhaiysah came and told them that 'Abdullah bin Sahl had been killed and thrown into a well. He came to the Jews and said to them, ‘I swear by Allah that you have killed him.’ They replied, ‘We swear by Allah that we have not killed him.' Then Muhaiysah came along with his brother Huwaiysah and 'Abdur Rahman bin Sahl to the Prophet (ﷺ) and Muhaiysah started to talk. The Messenger of Allah (ﷺ) said to him, “Let an older one speak (take charge of this matter).” So Huwaiysah narrated what happened and then Muhaiysah spoke. The Messenger of Allah (ﷺ) said:
“Either they pay the Diyah of your companion or be ready for war.” The Messenger of Allah (ﷺ) wrote to them about this and they wrote back saying, ‘By Allah, we have not killed him.’ The Messenger of Allah (ﷺ) then said to Huwaiysah, Muhaiysah and 'Abdur Rahman bin Sahl, “Would you take an oath (that they killed him) and then you will be entitled to the Diyah of your companion” 'They answered, ‘No (as they did not witness the crime).’The Messenger of Allah then said, “Then the Jews should take an oath (that they are innocent).” They said, ‘They are not Muslims.’ The Messenger of Allah (ﷺ) thereupon paid the Diyah of the victim himself and sent them 100 camels. Sahl commented, ‘A red she-camel (of these 100 camels) kicked me.’ Agreed upon.
عَنْ سَهْلِ بْنِ أَبِي حَثْمَةَ, عَنْ رِجَالٍ مِنْ كُبَرَاءِ قَوْمِهِ, أَنَّ عَبْدَ اَللَّهِ بْنَ سَهْلٍ ومُحَيِّصَةَ بْنَ مَسْعُودٍ خَرَجَا إِلَى خَيْبَرَ مِنْ جَهْدٍ أَصَابَهُمْ, فَأُتِيَ مَحَيِّصَةُ فَأُخْبِرَ أَنَّ عَبْدَ اَللَّهِ بْنِ سَهْلِ قَدْ قُتِلَ, وَطُرِحَ فِي عَيْنٍ, فَأَتَى يَهُودَ, فَقَالَ: أَنْتُمْ وَاَللَّهِ قَتَلْتُمُوهُ.‏ قَالُوا: وَاَللَّهِ مَا قَتَلْنَاهُ, فَأَقْبَلَ هُوَ وَأَخُوهُ حُوَيِّصَةُ وَعَبْدُ اَلرَّحْمَنِ بْنُ سَهْلٍ, فَذَهَبَ مُحَيِّصَةُ لَيَتَكَلَّمَ, فَقَالَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-{ "كَبِّرْ كَبِّرْ" يُرِيدُ: اَلسِّنَّ, فَتَكَلَّمَ حُوَيِّصَةُ, ثُمَّ تَكَلَّمَ مُحَيِّصَةُ, فَقَالَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-"إِمَّا أَنْ يَدُوا صَاحِبَكُمْ, وَإِمَّا أَنْ يَأْذَنُوا بِحَرْبٍ".‏ فَكَتَبَ إِلَيْهِمْ فِي ذَلِكَ [كِتَابًا].‏ فَكَتَبُوا: إِنَّا وَاَللَّهِ مَا قَتَلْنَاهُ, فَقَالَ لِحُوَيِّصَةَ, وَمُحَيِّصَةُ, وَعَبْدِ اَلرَّحْمَنِ بْنَ سَهْلٍ: "أَتَحْلِفُونَ, وَتَسْتَحِقُّونَ دَمَ صَاحِبَكُمْ?" قَالُوا: لَا.‏ قَالَ: "فَتَحْلِفُ لَكُمْ يَهُودُ?" قَالُوا: لَيْسُوا مُسْلِمِينَ فَوَدَاهُ رَسُولَ اَللَّهِ ‏- صلى الله عليه وسلم ‏-مِنْ عِنْدِهِ, فَبَعَثَ إِلَيْهِمْ مَائَةَ نَاقَةٍ.‏ قَالَ سَهْلٌ: فَلَقَدْ رَكَضَتْنِي مِنْهَا نَاقَةٌ حَمْرَاءُ }  مُتَّفَقٌ عَلَيْهِ.‏  1‏ .‏‏1 ‏- صحيح.‏ رواه البخاري (7192)‏، ومسلم (1669)‏ (6)‏.‏