Section 4

Where in execution of a warrant of arrest and detention any person is arrested or is required to be further detained in prison after the expiration of any sentence of imprisonment passed upon him the officer executing the warrant shall without unnecessary delay, and in any case within twenty-four hours (excluding the time of any necessary journey) from the arrest or from the expiration of the sentence produce the person arrested, or so detained before a Magistrate who shall, upon production of the warrant duly signed and upon proof of the identity of the person arrested or detained with the person named in the warrant, by order endorsed on the warrant, commit the person to prison, there to be detained in accordance with the tenor of that warrant:

Provided that if the person proves that he is a citizen or an exempted person the Magistrate shall order the person to be released forthwith.