E/CN.4/1999/63/Add.3 page 5 “(2) A person in respect of whom directions may be given under any of paragraphs 8 to 14 above may be detained under the authority of an immigration officer pending the giving of directions and pending his removal in pursuance of any directions given. “(3) A person on board a ship or aircraft may, under the authority of an immigration officer, be removed from the ship or aircraft for detention under this paragraph; but if an immigration officer so requires the captain of a ship or aircraft shall prevent from disembarking in the United Kingdom any person who has arrived in the United Kingdom in the ship or aircraft and been refused leave to enter, and the captain may for that purpose detain him in custody on board the ship or aircraft. “(4) The captain of a ship or aircraft, if so required by an immigration officer, shall prevent from disembarking in the United Kingdom or before the directions for his removal have been fulfilled any person placed on board the ship or aircraft under paragraph 11 or 15 above, and the captain may for that purpose detain him in custody on board the ship or aircraft. [“(4A) A person in a vehicle may, where he has arrived in the United Kingdom through the tunnel system in that vehicle, under the authority of an immigration officer, be removed from the vehicle for detention under this paragraph.] “17.(1) A person liable to be detained under paragraph 16 above may be arrested without warrant by a constable or by an immigration officer. “(2) If: (a) a justice of the peace is by written information on oath satisfied that there is reasonable ground for suspecting that a person liable to be arrested under this paragraph is to be found on any premises; or (b) in Scotland, a sheriff, or a magistrate or justice of the peace, having jurisdiction in the place where the premises are situated is by evidence on oath so satisfied; he may grant a warrant authorizing any constable ... to enter, if need be by force, the premises named in the warrant for the purpose of searching for and arresting that person. “18.(1) Persons may be detained under paragraph 16 above in such places as the Secretary of State may direct (when not detained in accordance with paragraph 16 on board a ship or aircraft).” B. Immigration Service Instructions (non-statutory) 10. In addition, Immigration Service Instructions are issued to staff in relation to such detentions. These instructions are dated 3 December 1991 and 20 December 1994. Though these instructions are non-statutory in nature, they provide guidelines to officers in the course of the discharge of their duties. The policy statement in the guidelines grants temporary admission/relief