Iowa Code § 321.84

It shall be the duty of any peace officer who finds a vehicle or component part, the vehicle identification number or component part number of which has been altered, defaced, or tampered with, and who has reasonable cause to believe that the possessor of the vehicle or component part wrongfully holds it, to forthwith seize it, either with or without warrant, and deliver it to the sheriff of the county in which it is seized.