65Power to refuse or cancel clearance of ship or aircraft
(1)For the purpose of the detention thereof in pursuance of any power or duty conferred or imposed by or under any enactment, or for the purpose of securing compliance with any provision of the Customs and Excise Acts 1979 or of any other enactment or of any instrument made thereunder, being a provision relating to the importation or exportation of goods—
(a)the proper officer may at any time refuse clearance of any ship or aircraft; and
(b)where clearance has been granted to a ship or aircraft, any officer may at any time while the ship is within the limits of any port or the aircraft is at any customs and excise airport demand that the clearance shall be returned to him.
(2)Any such demand may be made either orally or in writing on the master of the ship or commander of the aircraft, and if made in writing may be served—
(a)by delivering it to him personally ; or
(b)by leaving it at his last known place of abode; or
(c)by leaving it on board the ship or aircraft with the person appearing to be in charge or command thereof.
(3)Where a demand for the return of a clearance is made as aforesaid—
(a)the clearance shall forthwith become void ; and
(b)if the demand is not complied with, the master of the ship or the commander of the aircraft shall be liable on summary conviction to a penalty of £100.