In Tabari's history, a somewhat different version of the incident is given. It is stated that Qamazban the son of Hurmuzan appeared as a witness before the Caliph. He stated that a day previous to the assassination of Umar, his father came across Firoz. A double edged dagger fell from the hands of Firoz. Hurmuzan had asked Firoz why he had that dagger with him. Firoz had given an evasive reply, but Hurmuzan warned him not to use the dagger as that would involve them all in trouble.
In view of the evidence of Qamazban it was established that the assassination of Umar was the sole act of Firuzan neither Hurmuzan nor Jafina were involved in the conspiracy in any way. Thereupon the Caliph decided that Qamazban could deal with Ubaidullah in any way he liked. Qamazban was originally of the view to murder Ubaidullah, but later he changed his view and pardoned him for the sake of God. Thereupon Uthman paid the blood money out of his pocket.