(1) Where the police officer may, without warrant, enter the premises notwithstanding that they are not a public place and may for the purpose of effecting entry to the premises use such force (but no more) as may be reasonably necessary.(a) a person whom a police officer believes on reasonable grounds to be committing or to have committed an offence under this Act in relation to a raw narcotic, a narcotic substance, a prohibited substance, a section 36 substance, or a prohibited plant (i) flees from the presence of the police officer while the police officer is endeavouring to arrest him or to exercise in respect of him any other power conferred by this Act on a police officer; and(ii) after fleeing from that presence, enters premises that are not a public place; and(b) the police officer, immediately after the person flees from his presence, pursues the person and the pursuit continues without interruption (2) In this section, premises includes a dwelling-house, a residential flat, and any other place used as a residence, whether temporarily or permanently.(3) In this section, section 36 substance means a substance to which section 36 applies.