(1) Any postal article sent by post in contravention of any of the provisions of this Act may be detained and either returned to the sender or forwarded to destination, in each case charged with such additional postage (if any), as the Central Government may, by rule, direct.
     (2) Any officer in charge of a post office or authorised by the Post Master General in this behalf may open or unfasten any newspaper or any book, pattern or sample packet, in course of transmission by post, which he suspects to have been sent by post in contravention of ¹[section 20, clause (a), or of] section 21 or of any of the provisions of this Act relating to postage.
     (3) Notwithstanding anything in sub-section (1)--
     (a) any postal article sent by post in contravention of the provisions of section 19 ²[or section 19A] may, under the authority of the Post Master General, if necessary, be opened and destroyed; and
     ³[(b) any postal article sent by post in contravention of the provisions of section 20 may be disposed of in such manner as the Central Government may, by rule, direct.]