If a claim has not been made for the return or possession of the vehicle by a person legally entitled to the vehicle within the immobilization or impoundment period pursuant to this article, the person who has possession of the vehicle shall submit an abandoned vehicle report as provided in section 28-4838. The immobilizing or impounding agency shall require the person who takes possession of a vehicle pursuant to this section to obtain a release for the vehicle from the immobilizing or impounding agency.