; and (B) whether any Missing Armed Forces Personnel record has been withheld by the office, other than in accordance with this Act. (3) Preservation No Missing Armed Forces Personnel record shall be destroyed, altered, or mutilated in any way. (4) Effect of previous disclosure A Missing Armed Forces Personnel record made available or disclosed to the public before the date of enactment of this Act may not be withheld, redacted, postponed for public disclosure, or reclassified. (5) Non-Federal records Except for the exclusion of names or identities in accordance with section 6, a Missing Armed Forces Personnel record created by an individual or entity that is not part of the Federal Government may not be withheld, redacted, postponed for public disclosure, or reclassified. (6) Withheld records For any Missing Armed Forces Personnel record that is withheld by a Government office from the Archivist or the Review Board, the head of the Government office shall submit an unclassified report to the Review Board and each appropriate committee of the Senate and the House of Representatives explaining the decision to withhold the record. (b) Custody of Missing Armed Forces Personnel records pending review During the period during which a Missing Armed Forces Personnel record is being reviewed by a Government office and any review activity by the Review Board relating to the Missing Armed Forces Personnel record is pending, the Government office shall retain custody of the Missing Armed Forces Personnel record for purposes of preservation, security, and efficiency, unless— (1) the Review Board requires the physical transfer of the Missing Armed Forces Personnel record for purposes of conducting an independent and impartial review