Where it is shown to the satisfaction of a justice of the peace, on sworn information in writing, that admission to premises specified in the information is reasonably required by a person employed by, or acting on the instructions of, the local housing authority—
the justice may by warrant under his hand authorise that person to enter on the premises for those purposes or for such of those purposes as may be specified in the warrant.
The justice shall not grant the warrant unless he is satisfied—
The power of entry conferred by the warrant includes power to enter by force, if need be, and may be exercised by the person on whom it is conferred either alone or together with other persons.
If the premises are unoccupied or the occupier is temporarily absent, a person entering under the authority of the warrant shall leave the premises as effectively secured against trespassers as he found them.
The warrant continues in force until the purpose for which the entry is required is satisfied.