All prohibitions and restrictions imposed by or under this Act on the import into India, the export from India and transhipment of narcotic drugs and psychotropic substances shall be deemed to be prohibitions and restrictions imposed by or under the Customs Act, 1962 (52 of 1962) and the provisions of that Act shall apply accordingly:

Provided that, where the doing of anything is an offence punishable under that Act and under this Act, nothing in that Act or in this section shall prevent the offender from being punished under this Act.