Musannaf Ibn Abi Shaybah

Hazrat Ubaidah (may Allah have mercy on him) says that Ibrahim (may Allah have mercy on him) stated: If a person commits a crime and joins the enemies, and then those people are granted amnesty. He (may Allah have mercy on him) said: They will be granted amnesty except for any item that is recognized as being in their possession; that item will be taken from them and returned to its owners. And the item will be taken which he had acquired through crime before joining the enemies.