Palestinian prisoners of Israel (or as used by the Israel Prison Service: Security prisoners) refers in this article to Palestinians imprisoned in Israel in the context of the Israeli–Palestinian conflict. The future of Palestinian prisoners detained by Israel is considered central to progress in the Israeli–Palestinian peace process. Cases of prison sentences include the charges of terrorism or being a member of an "illegal terrorist organization", such as Hamas or prior to the Oslo Accords the Palestine Liberation Organization, but according to some accounts also by political activism such as raising a Palestinian flag.