Musannaf Ibn Abi Shaybah

Ibn Shihab narrates that during the time of Umar ibn Khattab, a man from the tribe of Juhainah trampled a person from the tribe of Banu Ghifar, or the narrator said: a person from the tribe of Banu Ghifar trampled a man from the tribe of Juhainah. So the family of that man claimed that he died because of this. Umar then asked fifty people from the claimants to take an oath. They refused to take the oath, and those against whom the claim was made also refused to take the oath. So Umar decided on half of the blood money in this matter.