Iowa Code § 820.14: Arrest without warrant.

The arrest of a person may be lawfully made also by any peace officer or a private person, without a warrant upon reasonable information that the accused stands charged in the courts of a state with a crime punishable by death or imprisonment for a term exceeding one year, but when so arrested the accused must be taken before a judge or magistrate with all practicable speed and complaint must be made against the accused under oath setting forth the ground for the arrest as in section 820.13; and thereafter the accused’s answer shall be heard as if the accused had been arrested on a warrant.