Egyptian prisoners in Israel have begun an open-ended hunger strike to demand their release. The 65 Egyptians are held in a prison in various prisons in the Negev desert in the South of Israel. Ibrahim El-Darawi, head of the Palestinian Studies Centre in Cairo, said that the prisoners opted to begin a hunger strike because they want to be released, especially because he said they are detained for political and not criminal crimes. El-Darawi added that the prisoners are angry because they were not among those swapped for Ilan Grapel, the Israeli-American who was detained in Egypt in June 2011 on charges of espionage. In October 2011, Grapel was released in exchange for 25 Egyptian prisoners in Israel.