Ariz. Rev. Stat. § 13-3900
A private person who has made an arrest shall without unnecessary delay take the person arrested before the nearest or most accessible magistrate in the county in which the arrest was made or deliver the person arrested to a peace officer, who shall without unnecessary delay take the person arrested before either the nearest or most accessible magistrate in the county in which the arrest occurs or, if the offense that the person is being arrested for was committed in another county, before either the nearest or most accessible magistrate in the county in which the arrest occurs or a magistrate in the county where the offense was committed. The private person or peace officer who takes the person arrested before the magistrate shall make before the magistrate a complaint, which shall set forth the facts showing the offense for which the person was arrested. If the peace officer cannot make the complaint, the private person who delivered the person arrested to the peace officer shall accompany the peace officer before the magistrate and shall make to the magistrate the complaint against the person arrested.
A.R.S. § 13-3900