Abu Dawud Book 13, Hadith Number 3037.
Narated By Umar ibn al-Khattab : Amr ibn Aws and AbulSha’tha’ reported that Bujalah said: I was secretary to Jaz’ ibn Mu’awiyah, the uncle of Ahnaf ibn Qays.
A letter came to us from Umar one year before his death, saying: Kill every magician, separate the relatives of prohibited degrees from the Magians, and forbid them to murmur (before eating). So we killed three magicians in one day, and separated from a Magian husband his wife of a prohibited degree according to the Book of Allah.
He prepared abundant food and called them, and placed the sword on his thigh. They ate (the food) but did not murmur. They threw (on the ground) one or two mule-loads of silver. Umar did not take jizyah from Magians until AbdurRahman ibn Awf witnessed that the Apostle of Allah (PBUH) had taken jizyah from the Magians of Hajar.