The UN special coordinator for the Middle East Peace Process Robert Serry said he is following "with concern" the case of hunger-striker Khader Adnan, who is held in administrative detention by Israeli occupation forces. In a statement, Serry called on Israel "to do everything in its power to preserve the health of the prisoner and resolve this case while abiding by all legal obligations under international law." During a visit in early February, UN secretary-general Ban Ki-moon''s discussed the issue of Adnan''s hunger strike with Palestinian Authority Minister of Prisoners Affairs Issa Qaraqe, the statement from Serry said. His office "is following up on some of the issues related to the question of prisoners, particularly on the use of administrative detention, which should only be employed in exceptional circumstances." Al-Sheikh Khader Adnan, a leader in the Islamic Jihad movement, has been on hunger strike since 18 December in protest against his ill-treatment, the conditions of his detention, and the policy of administrative detention. According to Amnesty International, administrative detention is a procedure under which detainees considered a threat to Israeli security are held without charge or trial for periods of up to six months and can be renewed indefinitely.