It is narrated from Hazrat Furat bin Hayan that the Prophet had ordered his killing because he was a spy and ally of Abu Sufyan. Furat passed by a group of the Ansar and he said, "I am a Muslim." They went and informed the Prophet (peace be upon him), "O Messenger of Allah (peace be upon him)! He claims that he is a Muslim." The Prophet (peace be upon him) said, "Some men among you are such that we trust their oath and hand them over according to their oath. Furat bin Hayan is among them."