 Amnesty International is also concerned that prisoners of conscience are being "held solely for the non-violent exercise of their right to freedom of expression and association".According to B'Tselem there are currently 645 Palestinians being held under administrative detention by the Israel Prisons Service and 105 by the IDF.Most are kept in the West Bank in Ofer Military Camp or in the Ansar 3/Ketziot Military Camp in the Negev desert.