R.I. Gen. Laws § 44-9-20: City or town treasurer’s release.

If land sold to a city or town for nonpayment of taxes, which has not been assigned, is redeemed, the treasurer shall sign, execute, and deliver on behalf of the city or town a release of all the right, title, and interest, which it acquired by the purchase in and to the land redeemed. The delivery of the instrument shall extinguish all right and title under the collector’s deed. If a person other than the owner of the fee rightfully redeems, the instrument when duly recorded shall be notice to all persons of the payment. If the amount so paid for redemption is paid by a holder of a mortgage on the premises, pays the amount so paid may be added to the mortgage debt (Form 3).