(1) An authorisation under this subsection authorises any constable in uniform to stop a vehicle in an area or at a place specified in the authorisation and to search -
(b) the driver of the vehicle;
(c) a passenger in the vehicle;
(d) anything in or on the vehicle or carried by the driver or a passenger.
(2) An authorisation under this subsection authorises any constable in uniform to stop a pedestrian in an area or at a place specified in the authorisation and to search -
(a) the pedestrian;
(b) anything carried by him.
(3) An authorisation under subsection (1) or (2) may be given only if the person giving it considers it expedient for the prevention of acts of terrorism.
(4) An authorisation may be given -
(a) where the specified area or place is the whole or part of a police area outside Northern Ireland other than one mentioned in paragraph (b) or (c), by a police officer for the area who is of at least the rank of assistant chief constable;
(b) where the spe