—(1) The competent authority may, with such assistants and workmen as are necessary, at any reasonable time, enter any land for the purpose of —
ascertaining whether there is, or has been, a contravention of this Act;
ascertaining whether any of the functions conferred by this Act on the competent authority or the Minister should or may be exercised; or
taking any action or carrying out any work authorised or required by or under this Act.
(2) The competent authority may take photographs of the land and any property or material found thereon and such other steps as he may consider necessary without involving any search or seizure of any premises, thing or person.
(3) The occupier of any premises shall, if required by the competent authority —
give his name and address;
provide proof of his identity; and
give the name and address of the owner of the premises, if known.
(4) Any person who wilfully obstructs the competent authority in the performance of any matter or thing which he is authorised to do by this section or fails to comply with the requirement under subsection (3) shall be guilty of an offence and shall be liable on conviction to a fine not exceeding $5,000 or to imprisonment for a term not exceeding 6 months or to both.
(5) A police officer may arrest without warrant any person who has committed or whom he reasonably suspects to have committed an offence under subsection (4) if —
the person declines to give his name and address; or
there is reason to doubt the accuracy of the name and address, if given.
(6) A person arrested under this section may be detained until his name and address are correctly ascertained except that no person so arrested shall be detained longer than is permitted by written law and is necessary for bringing him before a court unless the order of a court for his detention is obtained.